Leviticus 10:10

And that ye may put difference between holy and unholy,
&c.] That being sober they might be able to distinguish between the one and the other; which a drunken man, having his mind and senses disturbed, is not capable of; as between holy and unholy persons, and between holy and unholy things; particularly, as Aben Ezra interprets it, between a sacred place and one that is common, and between a holy day and a common week day; the knowledge and memory of which may be lost through intemperance; and so that may be done in a place and on a day which ought not to be done, or that omitted on a day and in a place which ought to be done:

and between unclean and clean;
between unclean men and women, beasts and fowls, and clean ones; and between unclean things in a ceremonial sense, and those that are clean, which a man in liquor may be no judge of: hence, as the above writer observes, after this section follow laws concerning fowls clean and unclean, the purification of a woman after childbirth, the leprosy in men, garments and houses, and concerning profluvious and menstruous persons; all which the priests were to be judges of, and therefore ought to be sober.