The idea of conversion to a Torah life has been around since the time of Abraham. During the time of Abraham he was given the promise of the eternal covenant with God which would be passed down through his son Isaac.

God further said to Abraham, “As for you, you and your offspring to come throughout the ages shall keep My covenant. Such shall be the covenant between Me and you and your offspring to follow which you shall keep: every male among you shall be circumcised. You shall circumcise the flesh of your foreskin, and that shall be the sign of the covenant between Me and you. And throughout the generations, every male among you shall be circumcised at the age of eight days. As for the homeborn slave and the one bought from an outsider who is not of your offspring, they must be circumcised, homeborn, and purchased alike. Thus shall My covenant be marked in your flesh as an everlasting pact.” (Genesis 17:9-13)1

We learn from Josephus that Abraham publically taught monotheism.

…he determined to renew and to change the opinion all men happened then to have concerning God; for he was the first that ventured to publish this notion, That there was but one God, the Creator of the universe; and that, as to other [gods], if they contributed any thing [sic] to the happiness of men, that each of them afforded it only according to his appointment, and not by their own power. (Antiquities of the Jews, 1.7.1)2

We also see that Abraham’s descendants took wives from amongst the relatives of Abraham as well as – we can assume – the nations surrounding them. In antiquity the wives would take on the religious beliefs of the husband. So, we can see that Abraham taught his son and grandson monotheism which was then passed on also to their wives who also became monotheists. There was no formal “conversion” at that time and the only requirement was that of male circumcision in order to enter into the covenant between God and Abraham and his descendants.

The idea of conversion to a life of following Torah – which includes the covenant with Abraham – came about during the giving of the Torah. Becoming a Yehudi (one who worships the Eternal One) did not officially start until the revelation at Mount Sinai. We are told that a mixed multitude came out of Egypt with Abraham’s descendants. We can easily deduce that at least some of those mixed multitude converted to what would ultimately come to be known as Judaism. We can see this clearly with Caleb.

…none except Caleb son of Jephunneh the Kenizzite and Joshua son of Nun, for they remained loyal to the Eternal One. (Numbers 32:12)1

…none except Caleb son of Jephunneh; he shall see it, and to him and his descendants will I give the land on which he set foot, because he remained loyal to the Eternal One. (Deuteronomy 1:36)1

The Kenizzites were a people from the land of Canaan as described in Genesis 15:19. It is obvious that Caleb’s father was a gentile yet Caleb is shown as being one who “remained loyal to the Eternal One.” He is adopted into the tribe of Judah and is given a tract of land in Canaan (Numbers 34:19; Joshua 14:13). It is quite obvious that Caleb was a convert to Torah. There is however no record of his conversion so we cannot determine how he converted, only that he did indeed convert.

We do get a glimpse of conversion however in the story of Ruth.

But Ruth replied, “Do not urge me to leave you, to turn back and not follow you. For wherever you go, I will go; wherever you lodge, I will lodge; your people shall be my people, and your God my God. Where you die, I will die, and there I will be buried. Thus and more may the Eternal One do to me if anything but death parts me from you.” When [Naomi] saw how determined she was to go with her, she ceased to argue with her; and the two went on until they reached Bethlehem. (Ruth 1:16-19)1

We see clearly that Ruth made a plea to Naomi that she be permitted to return to Israel with Naomi. Naomi tried to dissuade her and tell her of the hardships that will await her yet Ruth insists on going with Naomi. The simple phrase the “your people shall be my people and your God my God” proved Ruth’s determination and her acceptance of God – and ultimately Torah. From this we get a glimpse as to how one would convert to Judaism during Biblical times.

The basis of conversion is found in the Torah.

If a stranger (ger) who dwells with you would offer the Passover to the Eternal One, all his males must be circumcised; then he shall be admitted to offer it; he shall then be as a citizen of the country. But no uncircumcised person may eat of it. There shall be one law for the citizen and for the stranger who dwells among you. (Exodus 12:48-49)1

Since Ruth is a female there is no need for circumcision in her case. But, we can see that there is one law for the citizen and for the stranger who dwells among the Israelites. Ruth attached herself to Naomi and as a result she went to dwell among the Israelites and was considered a righteous convert.

According to Japheth ben-Eli Ruth made an oath before Naomi to which she was bound.

Her oath, may the Lord do unto me thus and thus, and even more, is a curse oath; she undoubtedly mentioned the things which were to happen to her if she violated her oath, but the narrator omitted them for the sake of brevity. (Karaite Anthology, p.96)3

How seriously were oaths taken in the Torah?

The vow of a widow or of a divorced woman, however, whatever she has imposed on herself, shall be binding upon her. (Numbers 30:10)1

Ruth became bound by this oath she made to Naomi. If she breaks that oath she shall be cut off from her people – in this case, the Israelites whom she has adopted.

We can plainly see just from these examples that conversion was always an option in Judaism. So how is conversion done in the post-Temple era?

According to Nehemiah Gordon, for those wishing to convert to Karaite Judaism he or she must accept the three fundamental principles of Karaite Judaism.4

1. Believe in the Eternal One as the only God and renounce all others.

2. Believe in the Tanakh as the words of the Eternal One and the only religious authority – renounce all other writings, doctrines, and creeds as words of men.

3. Study and keep the Tanakh while striving to interpret the Tanakh according to its peshat (plain) meaning.

In addition, the person will also need to accept the principles expressed in the ancient Karaite Vow:

By the covenant of Mount Sinai and the statutes of Mount Horev I will keep the holy appointed times of YHVH according to the New Moon and the finding of the Aviv in the Holy Land of Yisrael, when possible.4

According to the Hakhamim of the Karaites we learn from Exodus 12:48-49 the following regarding conversion5:

1. The potential convert must live in a Karaite community (although this is not necessarily a requirement today).

2. All males must be circumcised.

3. All converts must purify themselves and their homes.

4. A period of learning in (or with) a Karaite community must take place.

5. Conversion candidates must refrain from celebrating Passover until their conversion is complete.

6. Upon finalizing the conversion the candidate must make a public declaration of his/her intent to convert and leave all other faith systems.

According to Rabbinic Judaism conversion includes three things:

1. Circumcision for the male

2. Ablution (immersion) for both male and female

3. Proper witnesses as to the conversion

We see these three requirements listed in the Talmud:

R. Hiyya b. Abba stated in the name of R. Johanan: A man can never become a proselyte unless he has been circumcised and has also performed the prescribed ritual ablution. Is not this obvious? [In a dispute between] an individual and a majority the halachah is, surely, in agreement with the majority! — The expression ‘Sages’ is in fact meant for ‘R. Jose’. For it was taught: If [a proselyte] came and stated, ‘I have been circumcised but have not performed ritual ablution’ he is ‘permitted to perform the ablution and [the proper performance of the previous circumcision] does not matter; so R. Judah. … R. Hiyya b. Abba stated in the name of R. Johanan: The initiation of a proselyte requires the presence of three men; for law has been written in his case. (B. Talmud – Yevamoth 46b)6

Rambam (Maimonides) also speak of these requirements and adds more specifics to them in his Mishneh Torah (M.T. Issurei Biah 14:1-6) 7:

1. Make sure the person has no ulterior motives

2. Remind the person that the Jews are persecuted

3. Tell the person the fundamentals of the faith

4. Teach the person some of the easy mitzvot and some of the more difficult mitzvot

5. Teach the person the curses and blessings of following the mitzvot

6. The male must be circumcised

7. The male and female must immerse before a Beit Din

One difference between the Talmudic rules regarding conversion and the Tanakh rules is really the Beit Din. According to the Tanakh any Yehudi may be a witness but according to the Talmudic rules, only certain people can be on a Beit Din. The other difference is that of ablution. While today Karaite Judaism does have some Hakhamim who insist on immersion (which can be immersion in a living body of water or even a running shower) this is not a necessary part of the conversion process as it is in the Talmudic conversion process.

The process of conversion in both the Karaite and the Rabbinic worlds today takes at least a year. The much simpler process in the Tanakh has been replaced in both sects. If you are interested in converting please use the links in the sidebar to contact a Hakham (Karaite) or Rabbi (Rabbinic).


1David Stein (ed.). JPS Hebrew-English Tanakh. Philadelphia: Jewish Publication Society, 1999.
2William Whiston (trans.). The Works of Flavius Josephus., 1737. []
3Leon Nemoy (ed.). Karaite Anthology: Excerpts from the Early Literature. New Haven: Yale University Press, 1980.
4Nehemia Gordon. Conversion FAQ., n.d.  []
5al-Qirqisani Center. An Introduction to Karaite Judaism: History, Theology, Practice, and Custom. Troy, NY: al-Qirqisani Center for the Promotion of Karaite Studies, 2003.
6Halakhah.Com. Yevamoth., n.d. []
7Eliyahu Touger. Mishneh Torah: Issurei Biah., n.d. []