Leviticus 10:8-11

8And Jehovah spake unto Aaron, saying, 9Drink no wine nor strong drink, thou, nor thy sons with thee, when ye go into the tent of meeting, that ye die not: it shall be a statute for ever throughout your generations: 10and that ye may make a distinction between the holy and the common, and between the unclean and the clean; 11and that ye may teach the children of Israel all the statutes which Jehovah hath spoken unto them by Moses.