The Ten Commandments, also known as the Decalogue, are a set of biblical principles relating to ethics and worship, which play a fundamental role in the Abrahamic religions. The Ten Commandments appear twice in the Hebrew Bible, in the books of Exodus and Deuteronomy. The commandments include instructions to worship only God, to honour one's parents, and to keep the sabbath day holy, as well as prohibitions against idolatry, blasphemy, murder, adultery, theft, dishonesty, and coveting.