Leviticus 22 1
The LORD said to Moses,
"Tell Aaron and his sons to be very careful with the sacred gifts that the Israelites set apart for me, so they do not bring shame on my holy name. I am the LORD.
Give them the following instructions.
"In all future generations, if any of your descendants is ceremonially unclean when he approaches the sacred offerings that the people of Israel consecrate to the LORD, he must be cut off from my presence. I am the LORD.
"If any of Aaron's descendants has a skin disease 
or any kind of discharge that makes him ceremonially unclean, he may not eat from the sacred offerings until he has been pronounced clean. He also becomes unclean by touching a corpse, or by having an emission of semen,
or by touching a small animal that is unclean, or by touching someone who is ceremonially unclean for any reason.
The man who is defiled in any of these ways will remain unclean until evening. He may not eat from the sacred offerings until he has bathed himself in water.
When the sun goes down, he will be ceremonially clean again and may eat from the sacred offerings, for this is his food.
He may not eat an animal that has died a natural death or has been torn apart by wild animals, for this would defile him. I am the LORD.
"The priests must follow my instructions carefully. Otherwise they will be punished for their sin and will die for violating my instructions. I am the LORD who makes them holy.
"No one outside a priest's family may eat the sacred offerings. Even guests and hired workers in a priest's home are not allowed to eat them.
However, if the priest buys a slave for himself, the slave may eat from the sacred offerings. And if his slaves have children, they also may share his food.
If a priest's daughter marries someone outside the priestly family, she may no longer eat the sacred offerings.
But if she becomes a widow or is divorced and has no children to support her, and she returns to live in her father's home as in her youth, she may eat her father's food again. Otherwise, no one outside a priest's family may eat the sacred offerings.
"Any such person who eats the sacred offerings without realizing it must pay the priest for the amount eaten, plus an additional 20 percent.
The priests must not let the Israelites defile the sacred offerings brought to the LORD
by allowing unauthorized people to eat them. This would bring guilt upon them and require them to pay compensation. I am the LORD who makes them holy."
Worthy and Unworthy Offerings 17
And the LORD said to Moses,
"Give Aaron and his sons and all the Israelites these instructions, which apply both to native Israelites and to the foreigners living among you.
"If you present a gift as a burnt offering to the LORD, whether it is to fulfill a vow or is a voluntary offering,
will be accepted only if your offering is a male animal with no defects. It may be a bull, a ram, or a male goat.
Do not present an animal with defects, because the LORD will not accept it on your behalf.
"If you present a peace offering to the LORD from the herd or the flock, whether it is to fulfill a vow or is a voluntary offering, you must offer a perfect animal. It may have no defect of any kind.
You must not offer an animal that is blind, crippled, or injured, or that has a wart, a skin sore, or scabs. Such animals must never be offered on the altar as special gifts to the LORD.
If a bull 
or lamb has a leg that is too long or too short, it may be offered as a voluntary offering, but it may not be offered to fulfill a vow.
If an animal has damaged testicles or is castrated, you may not offer it to the LORD. You must never do this in your own land,
and you must not accept such an animal from foreigners and then offer it as a sacrifice to your God. Such animals will not be accepted on your behalf, for they are mutilated or defective."
And the LORD said to Moses,
"When a calf or lamb or goat is born, it must be left with its mother for seven days. From the eighth day on, it will be acceptable as a special gift to the LORD.
But you must not slaughter a mother animal and her offspring on the same day, whether from the herd or the flock.
When you bring a thanksgiving offering to the LORD, sacrifice it properly so you will be accepted.
Eat the entire sacrificial animal on the day it is presented. Do not leave any of it until the next morning. I am the LORD.
"You must faithfully keep all my commands by putting them into practice, for I am the LORD.
Do not bring shame on my holy name, for I will display my holiness among the people of Israel. I am the LORD who makes you holy.
It was I who rescued you from the land of Egypt, that I might be your God. I am the LORD."