Leviticus 18:3, 27-30

You shall not do what is done in the land of Egypt where you lived, and you shall not do what is done in the land of Canaan where I am bringing you. You shall not follow their statutes (practices, customs).

(for all these repulsive acts have been done by the men who lived in the land before you, and the land has become defiled); [do none of these things] so that the land will not vomit you out, should you defile it, as it has vomited out the nation which has been before you. For whoever commits any of these repulsive acts, those persons who do so shall be cut off from among their people [excluding them from the atonement made for them]. So keep My command: do not practice any of the repulsive customs which have been practiced before you, so as not to defile yourselves by them; I am the LORD your God.’ ”