Conversion to Judaism – Torah Sources for Process

The Aish Rabbi Replies

Thank you for raising this fundamental issue. You are right that the Torah never explicitly outlines a conversion process. However, as in many areas of Jewish law, the laws may be derived from various verses of the Torah, as noted by the Sages. I will provide a very brief outline of the laws and their sources below.

There are two famous cases of conversion in the Torah, and both of them are viewed by the Talmud (Keritot 9a, Yevamot 46-47) as precedents for the laws of conversion. The first is the Jewish people themselves at Mount Sinai. We formally became Hashem’s nation only when we accepted the Torah at Sinai – and the Sages liken that experience to conversion. We find that the Jews fulfilled all three requirements of conversion on that occasion:

• Acceptance of the mitzvot: This clearly occurred at Sinai when the Jews unanimously declared “we will do and we will hear” (Exodus 24:7).
• Circumcision: Shortly before the Revelation, at the time of the Exodus, the Jews offered and ate the Paschal Lamb. This required circumcision beforehand as the Torah forbids the uncircumcised from partaking in it (Exodus 12:44, 48).
• Immersion: The Talmud (Yevamot 46b) derives that the Jews underwent immersion before the Revelation. (This is based on Exodus 24:8 which describes the sprinkling of the blood on them at Sinai, and such sprinklings are always accompanied by immersion (for example, for the purification of impure people with the ashes of the Red Cow). See also Exodus 19:10.)
• (Note that the Talmud also derives that a new convert must bring a bird offering to the Temple, but conversion is valid without that. Converts will bring their offering God willing when the Temple is rebuilt.)

In addition, the Talmud (Yevamot 46b-47a) derives that conversion must be done in front of a Jewish court, either based on an allusion in Numbers 15:16 or one in Deuteronomy 1:16.

The second precedent in the Torah for conversion is the story of Ruth, which you mentioned (see Ruth 1:6-18). When Naomi returned to Israel from the land of Moab, Ruth (and initially the other daughter-in-law, Orpah) accompanied her. Naomi attempted to dissuade Ruth from coming, but Ruth expressed her strong desire to join the Jewish people, and so Naomi stopped discouraging her. Although the Book of Ruth does not mention Ruth’s actual conversion (which undoubtedly formally occurred after her arrival in Israel – see Ayelet HaShachar to Shabbos 113b), the Talmud (Yevamot 47) sees great significance in that entire episode. Naomi repeatedly attempted to discourage her daughters-in-law from following her. From this the Talmud infers that we must attempt to dissuade a potential convert. (See further Ruth Rabbah 2:16 that we discourage a convert three times – as did Naomi (vv. 8, 11 and 12).) However, even after the deterrence, Ruth persisted – and the Talmud accordingly rules that we do not dissuade a convert too much either. Once we are sure of the person’s sincerity, we accept him willingly.

The Talmud derives another principle from Ruth’s response to Naomi (vv. 16-17):

Do not urge me to leave you, to turn back from following you. For where you go, I will go; where you lodge, I will lodge; your people are my people, and your God is my God. Where you die, I will die, and there I will be buried…

From the wording of Ruth’s response, the Talmud derives what Naomi must have said to her beforehand. Namely, she informed her of some of the mitzvot – and Ruth, in her answers, implied that she fully intended to observe them. For example, Ruth answered “your God is my God” – implying that Naomi had told her that idolatry is forbidden. She said “where you go, I will go” when Naomi told her we do not travel too far beyond the city limits on Shabbat. More generally, the Talmud concludes based on this that we must do as Naomi – teaching a potential convert a selection of the mitzvos, some major and some minor – to ensure he is truly prepared to become observant. It is not necessary that the convert know every single mitzvah, but we test his resolve with a healthy sampling.

It has been noted the wisdom of the Talmud’s ruling (and Naomi’s behavior) that we teach the potential convert both major and minor mitzvot. The major ones inform him of the Torah’s most significant laws and their severity. The minor ones convey that Judaism even guides the finest details of our behavior, and that the Torah pertains to all aspects of our lives.

Another important principle is that although a convert does not have to know every law of the Torah at the time he converts, he must accept that he will fulfill every single law – whatever it may be. (This too parallels our declaration at Mount Sinai that “we will do and we will hear” – before we had actually found out what the Torah says.) The Talmud (Bechorot 30b) rules that if a potential convert accepts the entire Torah but refuses to accept even a single Rabbinical decree, he is not accepted. (See Shulchan Aruch Y.D. 268:3 and Biur HaGra Y.D. 124:5 that this is accepted in Jewish law. See likewise Igros Moshe O.C. V:18, Y.D. III:106. It should be noted that although we must not accept a convert who does not plan to observe all the mitzvot, according to many authorities if he is converted, the conversion is likely valid.)

Finally, it should be added that although the Talmud writes that we accept a convert immediately after he accepts the mitzvot, this is not the practice today. Today conversion courts are much more cautious – as a person might have become enamored with Judaism today but his excitement will wane tomorrow. The Talmud itself notes how problematic converts have been to the Jewish people (Yevamot 47b) – as too often they revert to their old idolatrous ways – and share their ways with their fellow Jews. Thus, today a potential convert will be required to study and practice for at least a year, while living in and becoming acclimated to a Jewish community. Only when he “graduates” his studies is he considered ready for proper conversion.