Nehemiah 13:1-3

1At that time the Book of Moses was read aloud in the hearing of the people, and in it they found the passage stating that no Ammonite or Moabite should ever enter the assembly of God,1 2because they had not met the Israelites with food and water, but had hired Balaam to call down a curse against them (although our God had turned the curse into a blessing).

3As soon as the people heard this law, they excluded from Israel all of foreign descent.