Keeping it in the Family: Intermarriage in the Tanakh

(1) When Adonai your God brings you to the land that you are about to enter and possess, and God dislodges many nations before you—the Hittites, Girgashites, Amorites, Canaanites, Perizzites, Hivites, and Jebusites, seven nations much larger than you— (2) and Adonai your God delivers them to you and you defeat them, you must doom them to destruction: grant them no terms and give them no quarter. (3) You shall not intermarry with them: do not give your daughters to their sons or take their daughters for your sons. (4) For they will turn your children away from Me to worship other gods, and Adonai’s anger will blaze forth against you and God will promptly wipe you out. (5) Instead, this is what you shall do to them: you shall tear down their altars, smash their pillars, cut down their sacred posts, and consign their images to the fire. (6) For you are a people consecrated to Adonai your God: of all the peoples on earth the Adonai your God chose you to be God's treasured people.

(4) An Ammonite or a Moabite shall not enter into the assembly of Adonai; even to the tenth generation shall none of them enter into the assembly of Adonai forever; (5) because they met you not with bread and with water in the way, when ye came forth out of Egypt; and because they hired against thee Balaam the son of Beor from Pethor of Aram-naharaim, to curse thee. (6) Nevertheless Adonai your God would not hearken unto Balaam; but Adonai your God turned the curse into a blessing unto thee, because Adonai your God loved thee. (7) Thou shalt not seek their peace nor their prosperity all thy days for ever. (8) Thou shalt not abhor an Edomite, for he is thy brother; thou shalt not abhor an Egyptian, because thou wast a stranger in his land. (9) The children of the third generation that are born unto them may enter into the assembly of Adonai.

(2) They have taken their daughters as wives for themselves and for their sons, so that the holy seed has become intermingled with the peoples of the land; and it is the officers and prefects who have taken the lead in this trespass.”

(2) Then Shecaniah son of Jehiel of the family of Elam spoke up and said to Ezra, “We have trespassed against our God by bringing into our homes foreign women from the peoples of the land; but there is still hope for Israel despite this. (3) Now then, let us make a covenant with our God to expel all these women and those who have been born to them, in accordance with the bidding of Adonai and of all who are concerned over the commandment of our God, and let the Teaching be obeyed.

(23) Also at that time, I saw that Jews had settled Ashdodite, Ammonite, and Moabite women; (24) a good number of their children spoke the language of Ashdod and the language of those various peoples, and did not know how to speak Judean.

Rava, is the reason for the prohibition “do not intermarry with them” a matter of sanctity? Rather, it is out of fear that the intermarried couple will have a child who will worship idolatry. This prohibition against intermarriage applies only against non-Jews, but if they convert, they are allowed for marriage.