And I contended with them, and cursed them, and smote certain of them, and plucked off their hair, and made them swear by God, saying, Ye shall not give your daughters unto their sons, nor take their daughters unto your sons, or for yourselves. Nehemiah 13:25

Trivia: According to Deuteronomy 23:2, who can't enter the congregation of the Lord, even to the tenth generation?