Deuteronomy 2:20

2:20 (That also is considered to be a land of the Rephaites. The Rephaites lived there originally; the Ammonites call them Zamzummites.

Deuteronomy 23:3

23:3 An Ammonite or Moabite may not enter the assembly of the Lord; to the tenth generation none of their descendants shall ever do so,