Hebrews 7:15-17

Verse 15. And it is yet far more evident. Not that our Lord would spring out of Judah, but the point which he was endeavouring to establish; that there must be a change of the priesthood, was rendered still more evident from another consideration. A strong proof of the necessity of such a change of the priesthood was furnished from the fact that the Messiah was to be of the tribe of Judah; but a much stronger because, as a priest, he was to be of the order of Melchizedek--that is, he was of the same rank with one who did not even belong to that tribe.

After the similitude, Resembling; that is, he was to be of the order of Melchizedek.
Verse 16. Who is made. That is, the other priest is made--to wit, the Messiah. He was made a priest by a peculiar law.

Not after the law of a carnal commandment. Not according to the law of a commandment pertaining to the flesh. The word carnal means fleshly; and the idea is, that the law under which the priests of the old dispensation were made was external, rather than spiritual; it related more to outward observances than to the keeping of the heart. That this was the nature of the Mosaic ritual in the main, it was impossible to doubt, and the apostle proceeds to argue from this undeniable truth.

But after the power of an endless life. By an authority of endless duration, That is, it was not concerned mainly with outward observances, and did not pass over from one to another by death, but was unchanging in its character, and spiritual in its nature. It was enduring and perpetual as a priesthood, and was thus far exalted above the service performed by the priests under the former dispensation.
Verse 17. For he testifieth. "That this is the true account of it is proved by the testimony of God himself, that he was to be a Priest for ever. Heb 5:6.

(a) "Thou art a Priest" Ps 110:4
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