Leviticus is one of the books in the Hebrew Bible and the Christian Old Testament. It is the third book in the Bible and is traditionally attributed to Moses, who is said to have written it during the Israelites' time in the wilderness. Leviticus primarily focuses on religious, ritual, and moral laws, as well as instructions for sacrifices and offerings. The book is named after the Latin word "levitas," which means "pertaining to the Levites," a tribe of Israelites who served as priests and assistants to the priests.