No one takes this honor upon himself; he must be called by God, just as Aaron was.
4. And no man, etc. There is to be noticed in this verse partly a likeness and partly a difference. What makes an office lawful is the call of God; so that no one can rightly and orderly perform it without being made fit for it by God.
We have here an account of the nature of the priestly office in general, though with an accommodation to the Lord Jesus Christ. We are told, I. Of what kind of beings the high priest must be. He must be taken from among men; he must be a man, one of ourselves, bone of our bones, flesh of our flesh, and spirit of our spirits...
Commenting on Hebrews 5:1-9
And no man taketh this honour to himself,.... That is, the honour of the priesthood: the office of the high priest was a very honourable one; it was a peculiar honour to Aaron, and his sons, to be separated unto it; their instalment into it was very grand and solemn; at that time they were anointed with oil, and clothed with glorious garments, and sacrifices...