Leviticus 21:23
Only he shall not go in unto the vail, nor come nigh unto the altar, because he hath a blemish; that he profane not my sanctuaries: for I the LORD do sanctify them. Only he shall not go in unto the vail, nor come nigh unto the altar, because he hath a blemish; that he profane not my sanctuaries: for I the LORD do sanctify them.
A priest with a physical blemish was barred from going in to the veil and from coming near the altar. The bar kept him from profaning the sanctuaries, for the Lord himself sanctified them. Sanctuary ministry brought close connection with God and therefore demanded holiness, purity, and freedom from blemish.
God's holiness and purity have not changed, and he is still particular about the holiness of those who serve him. The same requirement rests on ministers of Jesus, who must be holy and pure. Because their work brings them into close connection with God and entrusts them with care for the church, they are to be models of piety, meekness, humility, and purity in speech and action.