“‘Everyone who does any of these detestable things—such persons must be cut off from their people. Keep my requirements and do not follow any of the detestable customs that were practiced before you came and do not defile yourselves with them. I am the LORD your God.’” - Lev. 18:24-30 NIV
God was very explicit in his warning to Israel. They should not become conceited because they were inheriting the land from a people who didn't know the Lord God. If the Israelites failed to follow God's commands, they would be subject to the same consequences as the previous occupants of the land...they would be vomited out of the land. God's decrees and laws had to be kept, not only by the Israelites, but by the native born and aliens living along side the children of Israel. God's laws are God's laws. Detestable practices in God's sight defiles not only the people committing those acts, but the land as well.
History has shown this to be true. Through successive generations, those who once lived under God's favor became less God like and more like the natives and aliens of the land they inhabited together. Whenever that has occurred, God's people have sprung up in other lands that have not become defiled by what God has defined as detestable practices.
2010 Post - Leviticus 16-20: Set Apart