John Calvin Commentary Leviticus 20:22

"Ye shall therefore keep all my statutes, and all mine ordinances, and do them; that the land, whither I bring you to dwell therein, vomit you not out." — Leviticus 20:22 (ASV)

You shall therefore keep all my statutes. He now warns the Israelites, for the third time, not to imitate the Gentiles, and exhorts them to keep themselves within the limits of the Law. I have already pointed out that this was not done without reason, since otherwise they might have easily fallen away into approving their evil habits.

Moreover, so that they would not shake off God’s yoke, after He has said that the nations of Canaan were destroyed on account of similar abominations, He adds that they were made the inheritors of the land on condition that they should separate themselves from pagan nations.