This week's biblical reading details the first month of the Hebrew calendar, Nisan, beginning with the celebration of the new moon and emphasizing the laws concerning Pessah, our festival of freedom. But there is one "mystery" festival which requires explanation: "This day shall be for you a memorialâ€¦" (12:14). Of which day is the Scripture speaking? The classical commentator Rashi suggests it is the first day of the Pessah festival, the 15th of Nisan. But Pessah is seven days long (12:16), with the first and last days being "holy convocations" on which no physical work is permitted. Why single out the first day? Rabbi Abraham Ibn Ezra maintains that the verse is referring to the 14th of Nisan, the day before the start of Pessah, the day designated for the slaughter of the paschal lamb by the entire witness-congregation of Israel after the sun begins to set (12:6). According to this opinion, what are we celebrating on this day that makes it worthy as an eternal memorial? And perhaps included in the significance and purpose of this day is our having had to take the lamb on the 10th of Nisan, waiting to slaughter it until the 14th, and then placing its blood on our doorposts; moreover, we are enjoined to consume it entire (head, legs and innards), and prepare it roasted on the fire, neither raw nor boiled (12:8,4). Why all these detailed instructions? The astrological symbol of Nisan is Aries the Ram, linguistically linked to Ra, the sun-god of Egypt. Aries was particularly invoked in Nisan, the first month of spring, when the days were getting longer and the sun was getting stronger. A typical Pharaonic name was Raamses, or son of Ra; the very term Pharaoh may mean the House of Ra. And if indeed the ram (or lamb) symbolized the sun-god, we can readily understand the verse which records how Moses explained to Pharaoh why the Hebrews had to leave Egypt for three days in order to worship and sacrifice: "It would not be proper for us to do so [in Egypt], since we slaughter in a way which would be an abomination to Egypt before their eyes" (Exodus 8:22, see too Genesis 46:34). Nevertheless, right before the Exodus, the Almighty commands each Hebrew household to take a lamb (or ram) on the 10th of Nisan, the month of Aries, or Ra, and thus in effect capture the symbol of the Egyptian god before their very eyes; on the 14th day - after the Midrash teaches that they shall have had themselves circumcised, a symbol par excellence of blood commitment - they must place the blood of the ram on the doorposts of their homes, flaunting their sacrilegious act. They must then roast the lamb on a fire, causing maximum fragrance to waft into the streets while retaining all of the limbs "entire and intact," as the ultimate act of defiance. The Hebrews must earn their right to freedom - pay their exodus tax, as it were - by first "showing the way" out of idolatry, slaughtering the symbol of the Egyptian god, patron of consummate evil (ra from the Hebrews' perspective), who presided over hedonistic dictators and a slave culture imbedded in the very structure of society. Slaughtering the ram must have been a capital offence, so the Hebrews were placing their lives on the line on behalf of the God of freedom and morality. This then is the unique festival of the 14th of Nisan, which certainly deserves to be an eternal statute; it is a reminder of Hebrew mesirut nefesh - the commitment to pay the ultimate price on behalf of freedom. It is also a reminder that without such an ultimate commitment, freedom and redemption remain an unrealized dream. Thus from a biblical perspective, there are two distinct festivals: the one-day Festival of the Pessah sacrifice on the 14th of Nisan, and the seven-day Festival of Matzot from the 15th to the 22nd. One symbol remains to be explained, that of matza (unleavened bread) and hametz (leavened bread). Matza represents the poor bread eaten by the slaves in Egypt, who would return home hungry and exhausted after a day of manual labor, so anxious for sleep that they hadn't the energy to wait for their dough to rise. Matza was also the bread which the Hebrews took out of Egypt with them, and so it also became the symbol of freedom - freedom of movement, freedom of choice, and freedom of worship. And so matza is eaten together with the paschal sacrifice, and after the destruction of the Temple actually symbolizes the sacrifice (Mishneh Pessahim, 10 - the final matza of the Seder meal substitutes for the last taste of the paschal sacrifice eaten in Temple times). On the other hand, leaven - hametz - symbolizes the materialistic Pharaohs, who represented Ra the sun-god and utilized Hebrew slave labor for their own aggrandizement. Hence we are biblically commanded, "But, on the first day [of the Festival of the Paschal Sacrifice, the fourteenth day of Nisan] you must cause leaven to cease to be in your homesâ€¦" (Exodus 12:15). And the Hebrew word tashbitu (cease to be) can mean either to physically destroy or spiritually transform. The children of Abraham were put on this world to imbue it with compassionate righteousness and morality, to fight against - and ultimately destroy - the unbridled greed which fuels totalitarian despots and leads to the enslavement of their "vassal" subjects. This "leavening" must not be tolerated. If we can bloodlessly change regimes, if Amalek can be inspired to repent that would be optimal; but if such transformations are impossible, Pharaoh and his cohorts must die. Freedom and morality must prevail if humanity is to endure. The writer is the founder and chancellor of Ohr Torah Stone Colleges and Graduate Programs, and chief rabbi of Efrat.