Joshua 23:12-13

Else if ye do at all go back, and cleave unto the remnant of these nations, even these that remain among you, and make marriages with them, and go in unto them, and they to you; know for a certainty that Jehovah your God will no more drive these nations from out of your sight; but they shall be a snare and a trap unto you, and a scourge in your sides, and thorns in your eyes, until ye perish from off this good land which Jehovah your God hath given you.