A short introduction to kabbalah

Adapted from From Infinity to Man: The Fundamental Ideas of Kabbalah Within the Framework of Information Theory and Quantum Physics, by Eduard Shyfrin

 A view of the night sky.  (photo credit: Wikimedia Commons)
A view of the night sky.
(photo credit: Wikimedia Commons)
Kabbalah is a teaching based on the deep understanding of the multi-layered meaning of the Torah. It describes the creation of worlds by the Almighty, the theory of sefirot (Divine attributes), the laws of functionality and the connection of worlds, the creation of humankind, the human soul, and the role and tasks of humanity in Creation. 
The Jewish mystical tradition was born with Judaism itself. It assumed a variety of forms but has never stopped. The form of Kabbalah that we know today arose in Provence (Southern France) in the 12th century. Its founders were Rabbi Abraham ben Isaac of Narbonne,14 his son-in-law Abraham ben David (Raavad)15 and Isaac the Blind.16 Kabbalah subsequently became widespread among the Jewish communities in Spain. The most prominent centre for Kabbalah study was formed in Spain in the 13th century. It was known as the Gerona School, after the Catalonian town of Gerona where some eminent Kabbalists lived and studied. Among their number were Judah ben Yakar,17 Ezra ben Solomon,18 Azriel,19 Moses ben Nachman (Nachmanides or Ramban), Abraham ben Isaac Gerondi, and others.
In the 13th century, the Spanish Kabbalists included Abraham Abulafia,20 the founder of ‘Prophetic Kabbalah’. At the end of the 13th century, Moses ben Shem-Tov de Léon21 from Guadalajara published one of the main books of Kabbalah, Sefer ha’Zohar (‘The Book of Radiance’), ascribed to the Tannaim22 Rabbi Shimon bar Yochai.23 Another prominent 13th-century Kabbalist was Joseph Gikatilla.24 In the 14th century, the Kabbalist tradition was continued by Solomon ben Abraham Adret (Rashba),25 Isaac ben Todros26 and others. 
After the Jews were exiled from Spain in 1492, the Kabbalah centre moved to Safed in the Land of Israel. Among the Safed Kabbalists, most worthy of note were Moses Yaakov Cordovero,27 Joseph Caro,28 Arizal and Hayyim Vital.29 Later, the Kabbalist tradition was successfully continued by Hasidic tzadikim in Ukraine and Poland. Of particular interest is the founder of the Habad movement, Rabbi Shneur Zalman of Liadi, also known as Alter Rebbe [20]. 
The main books of Kabbalah include Sefer Yetzirah (‘The Book of Formation’), traditionally ascribed to our forefather Abraham, Sefer HaBahir, attributed to Rabbi Nehunya ben HaKanah,30 Sefer ha’Zohar, Pardes Rimonim by Moses Cordovero, the teachings of Arizal written by his pupil Hayyim Vital, and the works of the Alter Rebbe – the Tanya, Torah Or, and so on [25]. 
In Kabbalist traditions, the Almighty can be viewed in two states: Ein Sof (this refers to God’s infinite self-expression), and the Almighty in connection with His creation. The term Ein Sof first appeared in the works of Isaac the Blind and Azriel of Gerona. According to Kabbalah, the Almighty is only accessible to our understanding in connection with His creation. We cannot understand the Almighty in the state of Ein Sof. We do not find Him referred to in this way in the Torah and the Tanakh. In the state of Ein Sof, the Almighty is absolutely simple, whole, has no emotions or attributes, and is not subject to change. 
In the state of Ein Sof, the Creator is manifest as absolute perfection. He does not discern between good and evil, or heaven and earth. The epithets usually used in prayers cannot be applied to him (‘great’, ‘mighty’, etc.). According to Maimonides, in the state of Ein Sof God can only be understood in terms of negatives – for example, ‘never-ending’ – in view of His infinite nature [7]. 
In Kabbalah, Ein Sof is the root of all roots, which is in keeping with the description of God by some philosophers (Aristotle, Spinoza) who called Him the cause of all causes. Moses Cordovero wrote of the Almighty in the state of Ein Sof: ‘You should know that you must not use expressions such as “blessed”, “praised” and so on, with regard to Ein Sof, since He cannot be blessed or praised by others, because, in the state of Ein Sof, He is the One who blesses, praises and supports all – from the first (highest) point of emanation to the very lowest point. It is impossible to imagine, postulate, or say anything about Him – there is no justice, no mercy, no wrath, no change, no limits, and no process of any kind of quality whatsoever’ [25]. 
Within the reality of Ein Sof, no created being with an awareness of its own self can occur and exist. In order to allow created beings to appear with their own ‘self’, Ein Sof emanated and created a system of worlds based on the ten sefirot. 
 In the book Sefer Yetzirah, it says that everything was created by means of the twenty-two letters of the Hebrew alphabet and the ten sefirot, which were called numbers. It says: ‘Ten sefirot of nothing. Ten and not nine. Ten and not eleven.’ Later, it says: ‘The ten sefirot out of nothing. They appear like lightning and are without end. His word is in them, they are running and returning. Ten sefirot out of nothing. Their end enters into their beginning, and their beginning enters into their end, as a flame proceeds from coal’ [4]. 
In Kabbalah, a sefirah is allegorically depicted as a vessel filled with light. The sefirot are joined together in a system known as the tree of sefirot (Fig. 1). The sefirot system is the foundation of all worlds, and the channels for Divine Light. 
The first sefirah, Keter (the Crown), is the intermediary between Ein Sof and the rest of the sefirot system. It expresses the desire and will of the Creator.
In the next sefirah, Chochma (wisdom), eternal light is revealed in the form of finite and recognisable light in the sefirot system. Chochma represents the first, most primary element of creation that exists in the potential within Divine thought. Fig. 1. 
The tree of Sefirot 
The third sefirah, Binah (understanding), represents the realisation of the details inherent in the primordial Divine thought. The attributes of judgement and mercy are woven into the three highest sefirot, and only at the level of Binah does division occur, although the harmony between the attributes is retained.
The seven lower sefirot are divided into six midot and the sefirah of Malchut. The first triad of lower sefirot consists of Chesed, Gevurah and Tiferet. Chesed (kindness, love, expansion) corresponds to our forefather Abraham. Its characteristics are love, kindness and abundance. Gevurah (might, power, judgement, contraction) corresponds to our forefather Isaac. Its characteristics are restraint, brevity and judgement, whereby a person’s misdeeds and service are weighed up and a sentence is pronounced. The third sefirah, Tiferet (beauty), is a harmonising and balancing sefirah for Chesed and Gevurah. It is associated with our forefather Jacob, whose soul combined the characteristics of Abraham and Isaac. At this point, it is important to note the profound idea of the book Torah Or concerning the danger of unbalanced character traits. Thus, our forefather Abraham, who possessed Chesed that was not balanced by Gevurah, fathered Ishmael, who did not follow the way of his father. Our forefather Isaac, who possessed Gevurah that was not balanced by Chesed, fathered Esau, who also did not inherit his tradition. Only Jacob, whose characteristics were all balanced, had sons who all followed his way [9]. 
The next triad of sefirot is Netzach (victory), associated with Moses Rabbeinu, Hod (splendour), associated with Moses’ brother, Aaron the high priest, and Yesod (foundation), associated with Joseph, the son of Jacob. The main functions of Yesod are the harmonisation of Netzach and Hod, as well as the transfer of light from the highest sefirot to the sefirah of Malchut. Malchut (kingdom) is associated with King David. The light of all sefirot systems comes down in the sefirah of Malchut and, through it, is transferred to lower worlds. The Divine presence in the sefirah of Malchut is called Shekhinah.
According to the teaching of Arizal, apart from the sefirot there are also some fundamental principles of the formation of the world, known as partzufim (faces). The following partzufim are particularly notable: Abba (the Father, corresponds with the sefirah of Chochma), Imma (the Mother, corresponds with the sefirah of Binah), Arich Anpin (Long Face, therefore of long-lasting patience), Atik Yomin (‘Ancient of Days,’ which together with Arich Anpin corresponds with the sefirah of Keter), Zeir Anpin (literally short-faced, meaning impatient, corresponds with the six midot or qualities), Nukvah d’Zeir (the female hypostasis of Zeir, corresponds with the sefirah of Malchut). Sometimes Keter does not appear, and Daat (knowledge) is introduced instead. I will return to the other details of the sefirot system, their functional composition and their system of interaction, in later chapters. 
I have already mentioned that no created being with an awareness of its own ‘self’ is possible in Ein Sof. According to the teaching of Arizal, the first act of creation was tzimtzum. This is the ‘contraction’ of Ein Sof and formation of tehiru – the empty space. It contained only the remnants of Divine Light, known as reshimu. Compared with the infinite Ein Sof, tehiru was like a tiny spot, but it was from this that all levels of existence proceeded. Arizal explains that tzimtzum appears as Gevurah in the world. According to his teaching, before tzimtzum all the powers of the Almighty were in His infiniteness, and they were balanced without any division. However, for the creation of empty space, the Almighty concentrated the roots of Gevurah. 
Then, into this void, a line of light was directed – Ohr Ein Sof, from which worlds later developed. To this day there are many debates about how to understand the process of tzimtzum – literally or allegorically. Alter Rebbe rejected the literal understanding. According to his study, tzimtzum does not refer to the literal withdrawal of light, but to the reduced ability of the light to reveal itself before transitioning to a hidden state. He writes: ‘Therefore tzimtzum is called the “occurrence of empty space” or “a place deprived of light”, meaning a space where there is an absence of any kind of light, or a discovery that the light has gone away to its source and transitioned to potential existence.’ Additionally, Alter Rebbe comments that the concepts of reduction and concealment do not apply to the Almighty Himself, but only to His ‘light’ (self-expression) [9]. 
The first reality to emerge after tzimtzum was Adam Kadmon (primordial man). It contained all the sefirot as potential. Adam Kadmon is an intermediary realm between Ein Sof and the subsequent system of worlds. From the head of Adam Kadmon shone forth a light, which took various forms, in particular the outlines of letters and utterances. The light that proceeded from the ears, nose and mouth of Adam Kadmon spread out in a straight line and formed the world Akudim, in which all the sefirot were combined in a single vessel. The light that proceeded from the eyes was divided into separate sefirot. Thus, the world of Nekudim (spotted world) or the world of Tohu (chaos) was formed, where the sefirot did not interact with each other. 
It is said of the world of Tohu that ‘Its kings reigned in the land of Edom before the reign of the Children of Israel’. According to Alter Rebbe, the world of Tohu is the world of Gevurah, which ‘possesses enormous power and corresponds to the seven dead kings of Edom. That is why the ten sefirot of the world of Tohu are called kings’ [9]. In this world, a special event took place, which affected the whole structure of creation. Streams of Divine Light emanated into the sefirot of the world of Tohu. The eight lower sefirot were unable to withstand the strong beam of light and shattered into tiny pieces containing sparks of light, while the light itself returned to its source. This event was given the name ‘the shattering of the vessels’ (Shevirat ha-Keilim), and it is difficult to overestimate its importance. 
In Kabbalist literature, there are many explanations as to what caused the vessels to shatter. In total, there were 288 sparks of holiness that scattered and ‘fell’ into our material world. Arizal takes this number from the gematria of the word merahefet (hovered) from Bereishit 1:2. 
The fragments of the broken vessels, according to Arizal’s teaching, fell to the lower worlds, breaking into many more, even tinier pieces, and became the seeds of creatures with an awareness of their own ‘self’. Impure kelipot (‘husks’) belonging to sitra achra – the ‘other side’, i.e. evil – were formed from these same fragments. Alter Rebbe explains this by saying that the fragments possessed a large sense of their own ‘self’ and insufficient awareness of Divinity, hence the appearance of evil. 
In the example of the world of Tohu, the Almighty was convinced that creation cannot exist in such a form, since correction would be impossible in such a world. Creating the opportunity for correction required a fundamental change in the whole configuration of the sefirot system, in order to make interaction possible. 
Atzilut, Beriah, Yetzirah and Asiyah 
The description of the creation of these worlds is contained in the phrase of the prophet Yeshayahu: ‘All that is called by My name and for My glory, I created it, I formed it, I also made it’ (Yeshayahu, 43:7). The words ‘All that is called by My name’ refer to the world of Atzilut (the world of emanation); ‘created’ refers to the world of Beriah (the world of creation); ‘formed’ refers to the world of Yetzirah (the world of formation), and ‘made’ refers to our material world, Asiyah (the world of action). All four worlds contain a system of ten sefirot, which interact with each other. Moreover, every sefirah contains ten more sefirot, and so on, ad infinitum. (We will return to this question in subsequent chapters.) In the world of Atzilut, all the vessels of this world are united with the light, and there is no division between them [9]. There, the existence of anything except Divine Light is unthinkable. The lower sefirah of the world of Atzilut, Malchut, is the sefirah of Keter for the world of Beriah. Archangels, a few souls, and Gan Eden (paradise) are already appearing in the world of Beriah. The world of Yetzirah is populated by angels and souls. The world of Asiyah is populated by souls and people. 
The concept of ‘Divine Light’ is central to Judaism in general, and particularly to Kabbalah. Clearly an analogy between Divine Light and the physical light of our world is, if permissible, extremely limited. The book Torah Or contains the following definition: ‘The concept of “Divine Light” signifies revelation and proliferation. Because of it, the appearance of the source of the life force of all worlds becomes possible. The very essence of the concept of “light” is connected with revelation and proliferation. Divine Light, unlike the sefirot vessels, has no “self”. The same can also be said of the light of the Infinite: He Himself is a luminary, and His light is the revelation and proliferation of this luminary, i.e. the Divine life force’ [9]. There is a system of classification for the various forms of Divine Light. The light that is called mimalei (filling) and pnimi (internal) circulates within the system of worlds and sefirot. It is able to enter within an entity and be assimilated by it, joining with it from within in order to impart life and vitality to it. This form of light is, by its nature, concealed and limited. The light called sovev or makif (surrounding or encompassing) is the spiritual light of the Almighty, that is without limits. It cannot be perceived by a single creature. Its influence is unperceivable for Creation, and is the same for all. The infusion of light in a limited, hidden form begins in the sefirah of Chochma in the world of Atzilut. (I will write more about Divine Light in subsequent chapters.) While passing through the chain of worlds, the light takes part in the process of hishtalshelut (‘evolution’ and concealment of light). During this process, as the movement from the highest worlds towards the lowest ones takes place, there is a gradual ‘contraction’ – the concealment of light. As a result, it reaches our material world in a state of maximum concealment. Every time light passes from a higher level to a lower one, it passes through a parsa (a curtain), which is called hashmal (from the words for ‘to be silent’ and ‘to speak’). (We will return to this explanation, too, in subsequent chapters.) The light that descends from higher worlds to lower ones is called ‘direct light’. There is also ‘returning light’, which ascends from below to above. According to the teaching of Arizal, it arises as a result of the collision of direct light with an obstacle at the end of the stages, resulting in a kind of reflection. 
The question of the level of God’s omniscience and a person’s free will has been the cause of argument and debate in Judaism for many centuries. Alter Rebbe solves this contradiction by dividing the knowledge of the Almighty into two levels: higher and lower knowledge. Higher knowledge (the knowledge of Ein Sof), in his words, ‘refers to that which He knows and sees, as if making no impact at all’. Higher knowledge corresponds to the light of sovev. At the level of higher knowledge, there is no difference between good and evil, as neither reward nor punishment are produced [9]. This is the level of which Maimonides speaks when he says that the Almighty and His knowledge are one [7]. Alter Rebbe writes about this level as follows: ‘The level of higher knowledge is the source of forgiveness and mercy, since no flaw or sin can touch this level, which is higher than the vessels of the ten sefirot’ [9]. The book of Bamidbar says: ‘He does not look at evil in Jacob, and has seen no perversity in Israel’ (Bamidbar, 23:21). 
Lower knowledge is connected with the vessels and the midot, meaning it is in the system of worlds. At this level, reward and punishment takes place. This knowledge corresponds to the light filling the sefirot of the worlds of Atzilut, Beriah, Yetzirah and Asiyah. It can be said that lower knowledge ‘works within the regime of real time’. As Alter Rebbe comments, the Almighty does, of course, know everything in advance, but this knowledge is taken to mean higher knowledge, without the mediation of the vessels of the ten sefirot, which are called the ‘eyes of God wandering around on Earth’, by which the Creator views all the events from within time [9]. 
The Almighty has no name: how can the Giver of names have a name? However, we encounter Him under various names in the Torah. There are quite a lot of them, but we will look at just two – Havayah (the tetragrammaton – yud, hei, vav, hei) and Elohim. These names characterise the various levels of manifestation of the Almighty in relation to the creation of worlds and humanity. The name Havayah characterises the attribute of mercy. The letter yud corresponds to the sefirah of Chochma; the first hei refers to the sefirah of Binah; the letter vav signifies the six lower sefirot (midot); and the second hei indicates the sefirah of Malchut. 
The name Elohim corresponds to the Divine presence in our world, i.e. the sefirah of Malchut. Its effect is the concealment of Divine Light and a reduction of its intensity. Here, the quality of Gevurah is manifest, which corresponds to the name Elohim. The gematria of this name relates to the word ‘nature’ in Hebrew. Alter Rebbe writes: ‘After many contractions and concealments, carried out through the name of Elohim, Divine Light is clothed in created beings and gives them life, so that they may thus become “something”, that is, they will sense the seeming independence of their existence before the Divine “nothing”’ [9]. 
Before the sin of Adam, all the worlds were a single whole, through which Divine Light circulated freely. The side of evil, sitra achra, which occurred as a result of the shattering of the vessels (see ‘Worlds’, page 14), was completely separated from the side of holiness. Adam was placed in Gan Eden, and given the task of ‘working and guarding’ the garden – that is, to fulfil the commandments – and thus raise the sparks of holiness that had fallen into sitra achra back to their source. Therefore, Adam and Eve were present in Gan Eden in a state that wasn’t fully material (we will discuss this later). Adam possessed a single soul and authority over the world of Adam Kadmon. 
Several events occurred as a result of Adam’s fall. First of all, the unity of the worlds was broken, evil was mixed with good, and consequently, between the zone of kelipat (sitra achra) and the zone of holiness, a zone of kelipat nogah formed, where there is both good and evil. Adam’s soul lost its wholeness, and the bodies of Adam and Eve became material. The level of spirituality in the world of Asiyah diminished, and its material nature increased. The Divine presence in the world was substantially reduced. This is how the Alter Rebbe describes the process: ‘After Adam’s fall, it is said: “And the Lord God made for Adam and for his wife shirts of skin, and He dressed them” (Bereishit, 3:21), since before the fall, the concealment of light was particularly insignificant. However, after the fall, there was increased opposition; in other words, kelipat nogah appeared, which epitomises the clothes of skin’ [9]. Alter Rebbe explains the words of the Almighty that follow this action: ‘Adam has become like one of us, having the ability of knowing good and evil’ (Bereishit, 3:22). He writes that these words are addressed to the angels. Hence, the beings in higher worlds know the nature of good and evil. There, though, good and evil are not mixed together, but are separate [9]. If, after tasting the fruit of the tree of life, Adam had remained in Gan Eden, then evil would have been given the right to exist for eternity, which would have contradicted the intentions of the Almighty. This was the reason Adam and Eve were banished from Gan Eden after the fall. 
The soul is a created essence that gives life to all creation. According to the accepted classification in Judaism, a person’s soul is divided into several parts: nefesh (the vitalising soul), ruach (corresponds to the spirit and emotions), neshama (the intellectual part of the soul), chaya (the highest level of cognitive ability) and yechida (a spark of God – the highest level of the soul). Each part of the soul has its own root in higher worlds. Nefesh corresponds to the sefirah of Malchut, ruach to Zeir Anpin (the six lower sefirot), neshama to the sefirah of Binah, chaya to the sefirah of Chochma, and yechida to the sefirah of Keter. From my point of view, the most comprehensive ‘theory of the soul’ is the one developed by Alter Rebbe in the Tanya (‘The Book of the Intermediates’), Torah Or and others. It highlights the three component parts of the soul: Divine, animal and intellectual. Until its descent into the world, the Divine soul was part of the world of Atzilut. The purpose of its descending into lower worlds and being clothed in the animal soul of a human is to correct and raise up the animal soul. ‘Nevertheless, this descent of the soul is carried out for the sake of its subsequent ascent, since only by coming down is the soul able to study the Torah and fulfil the commandments’ [9]. The Divine soul never sins, although its love for the Almighty is constrained and limited by its investment within the animal soul and the body. 
All the intentions and actions of the animal soul are directed at our material world. It is ‘strong’ – its root is in the world of Tohu, the predecessor of Atzilut. Here, one of the main principles of Kabbalah is realised: ‘The lower the level where a created entity is located, the higher its spiritual root.’ 
Let us examine the structure of the soul, as presented by Alter Rebbe. According to his theory, the soul is ‘the whole and indivisible light, which cannot be divided into intellect and midot’. The latter serve merely as the ‘garments of the soul’: in other words, they belong to the soul but do not relate to its essence. Thus, the soul is a whole light whose garments consist of the ten sefirot. The structure of the soul corresponds to the structure of the higher spiritual worlds. Hence the words from Bereishit 1:26 about how man was created ‘in the image and likeness’ of the Almighty. 
There are a great many combinations of the ten sefirot that could occur, and which are like the DNA of a human soul. Which of the components of the human soul is given advantage depends on the correlation of the sefirot and the predominance of some trait or aspect over the others. On this topic, Alter Rebbe writes: ‘Intellect and emotion are “tools” that the soul uses, just as a woodcutter uses an axe. However, this does not all apply to the essence of a soul that has not been subject to any changes. … Intellect and midot (sefirot) are nothing more than powers of the soul, which are reflected in the body but do not capture the essence of the soul’ [9]. 
Where does the soul dwell? From my point of view, this question is incorrect, since the soul has no dimensions in time and space. The founder of Hasidism, Rabbi Israel Baal Shem Tov, emphasised that talking about the dwelling of the soul is wrong: instead, we should speak about where the soul’s revelation takes place. Both the animal and the Divine souls are clothed in sefirot. The six lower sefirot of the Divine soul (midot) are called yetzer ha-tov (positive impulse). The six lower sefirot of the animal soul are called yetzer ha-ra (negative impulse). There is a constant struggle between them. The task of the Divine soul is to turn the animal soul towards the Almighty, and towards studying the Torah and fulfilling the commandments. Because the animal soul is so strong, when its passions are redirected towards God, its love for the Almighty can have no limits. The third component part of the human soul – the intelligent soul – is, from the point of view of Alter Rebbe, an ‘intermediary’ between the Divine and the animal souls, and the means by which the Divine soul can influence the animal soul. 
In the book Sefer Yetzirah, it says that the Almighty created everything by means of the twenty-two letters of the Hebrew alphabet and the ten sefirot, known as numbers. Alter Rebbe writes: ‘The spiritual root of the letters is the sefirah of Keter, which is higher than Chochma and intellect. However, it is first revealed in Chochma, since it is impossible to recognise and understand a thing or a thought without the help of letters. The Torah, too, is clothed in letters, although the spiritual root of the letters of the Torah is incomparably higher than the Torah itself, since it is said of the Torah: “The Torah proceeds from Chochma”, while the root of the letters themselves is considerably higher – in the sefirah of Keter. The letters signify the attraction of influence from the highest level, whence the Torah appears’ [10]. Let us also note the fact that all worlds were created by the utterances of the Almighty, which are also made up of letters. 
According to the teaching of Arizal, the role of mankind is to implement the process of tikun (correcting the consequences of the shattering of the vessels and the sin of Adam) and attract Divine Light into the world. By means of Torah study, prayer, and fulfilling the commandments, a person must raise the sparks of holiness, which have fallen into the realm of sitra achra, back up to the higher worlds, turning darkness into light and thus destroying evil. It is worth noting that the commandments have their spiritual root in the sefirah of Keter, since they express the will and desire of the Almighty and are therefore higher than the Torah, which embodies the Divine wisdom (in the same way that, in the human being, will and desire are rooted higher in the psyche than intellectual understanding). Fulfilment of the commandments and prayer restore the broken connections in the higher worlds, allowing Divine Light to come into our world, and increasing its exposure. According to Kabbalah, by fulfilling the commandments a person ‘raises up the female waters’ (mayin nukvin – ascent of the holy sparks, fallen from the world of Tohu as a result of the shattering of the holy vessels) – i.e. the striving of Creation to unite with God – which leads to the restoration of the connection between the sefirah of Malchut (nukva) and Zeir Anpin (the six lower sefirot). This, in turn, leads to the restoration of connections between Zeir Anpin and the partzufim Abba and Imma, as a result of which an abundance of Divine Light (mayin dechurin) is attracted into the world. A person who breaks the commandments, on the other hand, brings about broken connections in the higher worlds, reduces the influx of Divine Light, and strengthens sitra achra. 
Prayer has a special significance in the process of tikun. Prayers were introduced by sages after the destruction of the Temple, and they were intended to replace sacrifices. Let us attempt to understand why. The Temple was a single, complete channel that stretched from the lower to the very highest worlds. Offerings in the Temple (inanimate matter, plants, animals and incense) passed through the entire chain of worlds to the level of Adam Kadmon, which connected it to the single whole. With the destruction of the Temple, this channel was also destroyed. Prayers spoken with deep spiritual purpose were called upon to fulfil the same function of restoring the broken connections of the worlds. However, prayers cannot be considered the full equivalent of offering sacrifices, since only in the case of the most righteous do they reach the world of Atzilut, while for some people they never even leave the confines of our world, Asiyah. 
The theory of continuous creation is one of the central moments in Judaism. It means that Ein Sof never stops creating worlds. In the event that the act of creation stops even for a single moment, all worlds would cease to exist and would dissolve into Ein Sof. 
A MEASURING ROD In the book Torah Or, Alter Rebbe describes the concept of botzina deqardinuta (the measuring rod). Its philosophical meaning is as follows. From the phrase: ‘How great are Your works, O Lord! You have made them all with wisdom (Chochma)’ (Tehillim, 104:24), Alter Rebbe concludes that Chochma carries within it the quality of Gevurah, which, in turn, corresponds to the ability to show every form with all its features, since the quality of Gevurah (judgement) signifies the limits of all things. The Alter Rebbe writes: ‘Botzina deqardinuta, called a measuring rod or ruler in the Zohar, is the spiritual root of chochma in the world of Atzilut’ [10]. Hence, in my opinion, it is possible to conclude that our world was created with the help of a measuring rod, and is therefore finite. It does not contain the infinite magnitudes. According to Kabbalah, the measuring rod is Gevurah Atik, the upper part of the sefirah of Keter of the world of Atzilut. 
The concept of ratzo and shov (ebb and flow) signifies two movements in opposite directions. Ratzo is the striving of the human soul to be united with the Almighty. Shov is the returning of the soul, and the attraction of light from the Almighty towards a person. 
14 Rabbi Abraham ben Isaac of Narbonne (c.1110–1158)– a Torah scholar and Kabbalist. France. 15 Abraham ben David of Posquières (Raavad; 1125–1198) – a pupil of Rabbi Abraham ben Isaac of Narbonne, eminent Torah sage, expert in Jewish law, and head of the Jewish sages of Provence. He is famous for his commentaries on the Babylonian Talmud and Maimonides’ Mishnah Torah. France. 16 Isaac the Blind (1160–1235) – a well-known Kabbalist of the Gerona School, and son of Abraham ben David. Many researchers believe that Isaac the Blind was the author of the book called the Bahir, the most important work on Kabbalah. 17 Judah ben Yakar – a Torah scholar, and one of the authors of the Tosafot – extensive commentaries on the Talmud. France. 18 Ezra ben Solomon – Torah scholar and Kabbalist. Spain. 19 Azriel (1160–1238) – Torah scholar, well-known Jewish Kabbalist of the Gerona School in the 12th century, and pupil of Isaac the Blind. Teacher of Nachmanides. 20 Abraham Abulafia (1240–c.1292) – an eminent Kabbalah scholar. He wrote 22 books on Kabbalah. The most well-known of these are: Sefer Sitrei Torah (‘Secrets of the Torah’), Chaye ha-Olam ha-Ba (‘Life in the World to Come’) and Or ha-Sekhel (‘Light of the Intellect’). Rabbi Abulafia continued the new path towards attaining hidden knowledge. He developed ‘Prophetic Kabbalah’ methods, leading him to achieve the level of prophet. 21 Moses ben Shem-Tov de Léon (1250–1305) – rabbi, Kabbalist, author and transcriber of Kabbalist books, including the Zohar. Spain. 22 Tanna (Aram. ‘teacher’) – a sage from the time of the compilation of the Mishnah. The views of the Tannaim concerning every instance of Jewish law are included in the Mishnah and the Baraita. The Gemara distinguishes between the Torah scholars of two periods – the Tannaim and the Amoraim (the latter lived at the time of the compilation of the Talmud). The era of the Tannaim began with the pupils of Shammai and Hillel. It lasted approximately two hundred years and included the years of King Herod’s rule, the destruction of the Temple, and the Bar Kokhba revolt. The era ended during the time of Rabbi Judah ha-Nasi, compiler and redactor of the Mishnah, and it was followed by the Amoraim era. 23 Rabbi Shimon bar Yochai (Rashbi; 2nd century AD) – one of the most prominent Jewish teachers of the law, a sage of the Torah, tanna, a founder of Kabbalah, and author of one of the main Kabbalist books, the Zohar. 24 Joseph ben Abraham Gikatilla (1248–1305 or later) – one of the representatives of the Spanish Kabbalah school. One of his most well-known works is Sha’are Ora (‘Gates of Light’). 25 Rabbi Solomon ben Abraham Adret (Rashba; c.1235–1310) – a pupil of Nachmanides, an authoritative sage of the 13th and 14th centuries, and a Jewish law expert. He officially held the post of Chief Rabbi of Barcelona, although he actually acted as chief rabbi of Spain. He wrote a range of commentaries on various Talmudic treatises, and compiled a new code of laws – Torat ha-Bayit ha-Aruk (‘The Complete Law of the House’) – and other books. 26 Isaac ben Todros – Spanish rabbi, Talmud scholar and doctor in the early 14th century. 27 Rabbi Moses Yaakov Cordovero (Ramak; 1522–1570) – one of the greatest Kabbalists of all time. He founded his own academy in Safed, where Arizal studied. His main work was Pardes Rimonim (‘Orchard of Pomegranates’). In this work, Ramak summarised and systematised three centuries of Kabbalist ideas, beginning with the publication of the Zohar. 28 Rabbi Joseph ben Ephraim Caro (1488–1575) – the greatest law teacher of all generations, the founder of the Shulchan Aruch (‘Set Table’) code and Beth Yoseph (‘House of Joseph’), a fundamental commentary on Jewish Laws. 29 Rabbi Hayyim bar Joseph Vital (1543–1620) – one of the greatest Kabbalists of all time. A pupil of Arizal and Rabbi Moses Cordovero. He wrote down the knowledge he had been given by Arizal in two large books: Etz Hayyim (‘Tree of Life’) and Etz Hadaat (‘Tree of Knowledge’). 30 Nehunya ben HaKanah – second generation tanna. Praised for his piety. His name is often associated with pursuing hidden wisdom. 
This article is part of a collaboration for the Kabbalat Shabbat Project with Eduard Shyfrin.