Deuteronomy 23:3-8

3An Ammonite or a Moabite shall not enter into the assembly of the LORD; even to the tenth generation shall none belonging to them enter into the assembly of the LORD for ever:

4because 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 Mesopotamia, to curse thee.

5Nevertheless the LORD thy God would not hearken unto Balaam; but the LORD thy God turned the curse into a blessing unto thee, because the LORD thy God loved thee.

6Thou shalt not seek their peace nor their prosperity all thy days for ever.

7Thou shalt not abhor an Edomite; for he is thy brother: thou shalt not abhor an Egyptian; because thou wast a stranger in his land.

8The children of the third generation that are born unto them shall enter into the assembly of the LORD.