Leviticus 18:26-28

Ye shall therefore keep my statutes and my judgments, and shall not commit any of these abominations; neither any of your own nation, nor any stranger that sojourneth among you: (for all these abominations have the men of the land done, which were before you, and the land is defiled;) that the land spue not you out also, when ye defile it, as it spued out the nations that were before you.