Num 20:26

“But what does this signify, that after Aaron was dead, the Lord commanded, not the whole people, but Moses alone, who is amongst the priests, to clothe Aaron's son Eleazar with the priest's garments, except that we should understand that priest must consecrate priest, and himself clothe him with the vestments, that is, with priestly virtues; and then, if he has seen that nothing is wanting to him of the priestly garments, and that all things are perfect, should admit him to the sacred altars. For he who is to supplicate for the people ought to be chosen of God and approved by the priests, lest there be anything which might give serious offence in him whose office it is to intercede for the offences of others. For the virtue of a priest must be of no ordinary kind, since he has to guard not only from nearness to greater faults, but even the very least. He must also be prompt to have pity, not recall a promise, restore the fallen, have sympathy with pain, preserve meekness, love piety, repel or keep down anger, must be as it were a trumpet to excite the people to devotion, or to soothe them to tranquillity.”