John Chrysostom : "For He of whom these things are spoken pertained to another tribe, of which no man gave attendance at the altar. For it is evident that our Lord sprang out of Judah, of which tribe Moses spake nothing concerning priests." I myself also say it, I know that this tribe of Judah had nothing of priesthood. For there is a transferring. And observe the mystery. First it was royal, and then it is become sacerdotal: so therefore also in regard to Christ: for King indeed He always was, but has become Priest from the time that He assumed the Flesh, that He offered the sacrifice. Thou seest the change, and the very things which were ground of objection these he introduces, as though the natural order of things required them. — Homily on Hebrews 13 Oecumenius : "For he of whom these things are spoken." It is certainly said concerning Christ, "You are a priest forever according to the order of Melchizedek." (Heb. 7:17) "belongs to another tribe." And so great, he says, is the change and interchange of both the law and the old covenant, that even of that tribe, which administered the old priesthood, there has been a change. For Christ is of another tribe, not of Levi but of Judah, which tribe, neither at any time served as a priest at the altar. — The Pseudo-Oecumenian Catena on Hebrews