Deuteronomy 23:3-4

No Ammonite or Moabite may enter the LORD’s assembly; none of their descendants, even to the tenth generation, may ever enter the LORD’s assembly. This is because they did not meet you with food and water on the journey after you came out of Egypt, and because Balaam son of Beor from Pethor in Aram-naharaim was hired to curse you.