For the priesthood being changed, there is made of necessity a change also of the law.
All Commentaries on Hebrews 7:12 Go To Hebrews 7
John Chrysostom
AD 407
And what is the meaning of what follows? For (he says) under [or upon] it the people have received the Law [or have been legislated for]. What is under it [&c.]? Orders itself by it; through it does all things. You cannot say that it was given to others, the people under it have received the law, that is, have used it, and did use it. You cannot say indeed that it was perfect, it did not govern the people; they have been legislated for upon it, that is, they used it.
What need was there then of another priesthood? For the priesthood being changed, there is of necessity a change of the law also. But if there must be another priest, or rather another priesthood, there must needs be also another law. This is for those who say, What need was there of a new Covenant? For he could indeed have alleged a testimony from prophecy also. This is the covenant which I made with your fathers [&c.]. Hebrews 8:10 But for the present he contends on the ground of the priesthood. And observe, how he says this from the first. He said, According to the order of Melchisedec. By this he excluded the order of Aaron. For he would not have said After the order of Melchisedec, if the other had been better. If therefore another priesthood has been brought in, there must be also [another] Covenant; for neither is it possible that there should be a priest, without a covenant and laws and ordinances, nor that having received a different priesthood He should use the former [covenant].
In the next place, as to the ground of objection: How could He be a priest if He were not a Levite? Having overthrown this by what had been said above, he does not even think it worth answering, but introduces it in passing. I said (he means) that the priesthood was changed, therefore also the Covenant is. And it was changed not only in its character, or in its ordinances, but also in its tribe. For of necessity [it must be changed] in its tribe also. How? For the priesthood being changed [or transferred ], from tribe to tribe, from the sacerdotal to the regal [tribe], that the same might be both regal and sacerdotal.
