'Defile' in the Bible

The people who do this will be blessed, the people who commit themselves to obedience, who observe the Sabbath and do not defile it, who refrain from doing anything that is wrong.

As for foreigners who become followers of the Lord and serve him, who love the name of the Lord and want to be his servants -- all who observe the Sabbath and do not defile it, and who are faithful to my covenant --