(Previously in Leviticus 21)
1.      Personal Qualifications
a.      Mourning
b.      Marriage
2.      Physical Fitness (without blemish)
3.      Professional Conduct

Service that was not admissible
And the Lord spoke to Moses, saying, 2 “Speak to Aaron and his sons so that they abstain from the holy things of the people of Israel, which they dedicate to me, so that they do not profane my holy name: I am the Lord. 3 Say to them, ‘If any one of all your offspring throughout your generations approaches the holy things that the people of Israel dedicate to the Lord, while he has an uncleanness, that person shall be cut off from my presence: I am the Lord . . . 9 They shall therefore keep my charge, lest they bear sin for it and die thereby when they profane it: I am the Lord who sanctifies them. Lev 21:1-9 (ESV)

Negligence that was not permissible
A lay person shall not eat of a holy thing; no foreign guest of the priest or hired worker shall eat of a holy thing . . . 14 And if anyone eats of a holy thing unintentionally, he shall add the fifth of its value to it and give the holy thing to the priest. 15 They shall not profane the holy things of the people of Israel, which they contribute to the Lord, 16 and so cause them to bear iniquity and guilt, by eating their holy things: for I am the Lord who sanctifies them.” Lev 21:10-16 (ESV)

Sacrifices that were not acceptable
And the Lord spoke to Moses, saying, 18 “Speak to Aaron and his sons and all the people of Israel and say to them, When any one of the house of Israel or of the sojourners in Israel presents a burnt offering as his offering, for any of their vows or freewill offerings that they offer to the Lord, 19 if it is to be accepted for you it shall be a male without blemish, of the bulls or the sheep or the goats. 20 You shall not offer anything that has a blemish, for it will not be acceptable for you. 21 And when anyone offers a sacrifice of peace offerings to the Lord to fulfill a vow or as a freewill offering from the herd or from the flock, to be accepted it must be perfect; there shall be no blemish in it. . . . 26 And the Lord spoke to Moses, saying, 27 “When an ox or sheep or goat is born, it shall remain seven days with its mother, and from the eighth day on it shall be acceptable as a food offering to the Lord. 28 But you shall not kill an ox or a sheep and her young in one day. 29 And when you sacrifice a sacrifice of thanksgiving to the Lord, you shall sacrifice it so that you may be accepted. 30 It shall be eaten on the same day; you shall leave none of it until morning: I am the Lord.

31 “So you shall keep my commandments and do them: I am the Lord. 32 And you shall not profane my holy name, that I may be sanctified among the people of Israel. I am the Lord who sanctifies you, 33 who brought you out of the land of Egypt to be your God: I am the Lord.” [1]
Lev 22:18-33

[1] The Holy Bible: English Standard Version. (2016). (Le 22:17–33). Wheaton, IL: Crossway Bibles.