For Priests, Discernment of Uncleanness Is Vital. They Must Not Approach Yahweh While Unclean Lest They Die (Leviticus 22:2-9).
“Speak to Aaron and to his sons, that they separate themselves from the holy things of the children of Israel, which they hallow to me, and that they profane not my holy name. I am Yahweh.”
Aaron and his sons must ensure that they see themselves as separate from the holy things of the children of Israel, which the children of Israel hallow to Yahweh. The sanctuary was not theirs, they were privileged to minister there. The holy things were not theirs, they were privileged to have a part in them. They had no automatic right to have contact with them. They may minister with them when they were clean, but not when they were unclean. Such things were God's and God's alone. Thus when they were unclean (verse 3) they must have nothing to do with them. They must see themselves as separate from those holy things in such a way that uncleanness barred them from them. Otherwise they would profane and make common the holy Name of Yahweh. Even Aaron and his sons must not presume on God.
“Say to them, Whoever he be of all your seed throughout your generations, who approaches to the holy things, which the children of Israel hallow to Yahweh, having his uncleanness on him, that person shall be cut off from before me. I am Yahweh.”
So even looking into the far future, if anyone of the seed of Aaron presumes, and approaches the holy things of Yahweh while ritually unclean, he is to be cut off from being a priest. For they must remember that God is Yahweh, the Holy One whose holy things must not be defiled.
“Whatever man of the seed of Aaron has a suspicious skin disease, or has an issue, he shall not eat of the holy things, until he is clean.”
This includes the fact that a man of the seed of Aaron is barred from eating the holy things until he is clean. This includes those who have a suspicious skin disease, and those who have an issue. They are unclean all the while that they have either.
Leviticus 22:4-7 (4b-7)
“And whoever touches anything which is unclean by the dead, or a man whose seed goes from him, or whoever touches any creeping thing, whereby he may be made unclean, or a man of whom he may take uncleanness, whatever uncleanness he has, the person who touches any such shall be unclean until the evening, and shall not eat of the holy things, unless he bathe his flesh in water, and when the sun is down, he shall be clean; and afterward he shall eat of the holy things, because it is his bread.”
Indeed all the laws of uncleanness apply equally to the priests. Touching anything that has had contact with death, a man emitting semen, any forbidden creeping thing, touching anyone who can convey uncleanness, whatever that uncleanness is, will render the priest unclean until the evening. He shall not eat of holy things until that uncleanness is dealt with. This will be by washing his flesh thoroughly in water and waiting until the evening. Then he may eat of holy things because it is his God-provided food.
“What dies of itself, or is torn of beasts, he shall not eat, to defile himself with it. I am Yahweh.”
They must also not eat anything that dies of its own accord, or anything that is torn by beasts. Both would defile them. And they must remember that God is Yahweh, the living God.
“They shall therefore keep my charge, lest they bear sin for it, and die in it, if they profane it. I am Yahweh who sanctifies them.”
So must they keep His charge, lest they receive punishment for any transgression or sin that they commit, a punishment which will result in death. To touch holy things while unclean would be to insult and disparage Yahweh and treat them as common. They must remember that the One Who has sanctified them is Yahweh. And He must not be approached with defilement.
Once more then we have an emphasis on the fact that all who would serve God must keep themselves from all forms of uncleanness. They must be pure in heart and mind and in outward living. They must avoid all that could defile them.