Although the Torah itself never makes any connection between the holiday of Shavuot and the great events that took place at Mount Sinai, later Judaism did, officially calling Shavuot “the time of the giving of our Torah.” And so it is that on Shavuot we read the description of those events, culminating with the Ten Commandments.The expression “the time of the giving of our Torah” is somewhat problematic, however, since neither the account in Exodus 19 nor the recapitulation in Deuteronomy 5 says that Israel received the Torah – i.e., the Five Books of Moses – at that time. It states that the Ten Commandments were revealed to the entire people then and that some other rules and laws were subsequently given to Moses, but that is all.The concept of a Divine book – the Torah – which existed even before the creation of the world and which was revealed in compete form at Sinai was the creation of later Jewish belief, found most specifically in the teachings of Rabbi Akiva and his disciples. The actual story really emphasizes something else of great importance.What it teaches is that this event at Sinai celebrates the making of a covenant, a mutually binding agreement in which Israel became God’s special treasure and the Lord became the God of Israel. It was a ceremony in which Israel became God’s people.The terms of the covenant were those found in the Decalogue.All of this is spelled out specifically in the events leading up to the Decalogue. As God says, “Now if you will obey Me faithfully and keep My covenant, you shall be My treasured possession among all the peoples... a kingdom of priests and a holy nation” (Exodus 19:5-6).The people have to agree to this contract, which they do when they answer, “All that the Lord has spoken we will do” (Exodus 19:8). Similarly, when retelling it in Deuteronomy, Moses says, “The Lord our God made a covenant with us at Horeb. It was not with our fathers that the Lord made this covenant, but with us, the living, every one of us who is here today” (Deuteronomy 5:2-3). “Covenant” – brit – is the important word. For the Torah, then, the central importance of the gathering at Sinai was really the making of this new covenant between God and Israel.An earlier covenant had been established between God and Abraham. “Walk in My ways and be blameless. I will establish My covenant between Me and you, and will make you exceedingly numerous” (Genesis 17:1-2). This “Covenant of the Patriarchs” – brit avot – granted Abraham the gift of becoming great in numbers and of inheriting the land of Canaan.This new covenant – the “Covenant of Sinai” – brit Sinai – goes beyond that. It binds the people to obey the commandments of the Lord. In a very real sense, this event was a mass conversion in which the Israelites were changed from simply an ethnic group into God’s people.The question so often asked, “Who is a Jew?” originated at that moment. Those who entered into the covenant became Jews – although the word “Jew” was not yet invented. Those descended from them were born into the covenant.How could others join this treasured people? The answer to that question evolved over the centuries. At first, non-Israelites who lived permanently in the Land of Israel observed some of the commandments and were given special privileges. Over time they gradually assimilated and without any fanfare became part of the assembly of Israel.There were also different rules for various ethnic groups. Because of their actions against the Israelites in the desert, Ammonites and Moabites were never permitted to join, while Edomites – kinsmen – and Egyptians, who gave us shelter in their land, were admitted after the third generation (Deuteronomy 23:4-9). The Book of Ruth – written at a later time – takes a different position, accepting a Moabite woman into the group immediately when she has indicated her identification with the people and the God of Israel – “Your people shall be my people and your God my God” (Ruth 1:16).But there was still no formal way of being accepted into the community.Sometime during the Second Temple period, conversion as we know it – i.e., a formal procedure for becoming a Jew – came into being. Going through this ceremony of acceptance, a non-Jew becomes a Jew, just as the Israelites became God’s people at Sinai. The famous stories told concerning potential proselytes who turned first to Shammai and then to Hillel in the first century BCE indicate that this was a recognized procedure, even if the two Sages differed as to what was required in order to be accepted.During the period before the Great Revolt that ended in 70 CE, Jews actively proselyted and many Romans became either full Jews or semi-proselytes.That all ended with the defeat of the revolt, and conversion to Judaism became a rarity. Later, when Christianity established itself as the official Roman religion, conversion to Judaism became illegal.In modern times conversion to Judaism became more common – as did Jewish conversion to Christianity.Unfortunately, recently, religious authorities, especially those in Israel, adopted procedures that went far beyond the actual requirements stated in Jewish law. This has had tragic consequences, especially in regard to massive immigration from the former Soviet Union, when hundreds of thousands of people with Jewish ancestry became Israelis but rabbinical authorities made no effort to help them became Jews. On the contrary, everything possible was done to make such a step difficult, if not impossible. Instead of welcoming them with outstretched arms, they were met with closed doors.Shavuot, when we first became Jews, and when we read the Book of Ruth containing a positive attitude toward acceptance into Judaism, is a good time to remind ourselves that Judaism truly welcomes those who wish to join us. If a Moabite woman could become the ancestress of King David and of the Messiah, we should not look with disdain at potential converts but, rather, do our best to bring them “under the wings of the Divine Presence.” ■ The writer, a former president of the international Rabbinical Assembly, is an author and lecturer who has lived in Jerusalem since 1973. Two of his books were awarded the National Jewish Book Prize as the best scholarly book of the year. His most recent book is Akiva: Life, Legend, Legacy (JPS), which is soon to be published in Hebrew.