John Calvin on Hebrews 7:15

15. And it is yet far more evident, etc. He proves by another argument, that the Law is abolished. He reasoned before as to the person of the priest, but now as to the nature of the priesthood, and the reason for which it was appointed. The ancient priesthood, he says, had to do with external rites; but in Christ’s priesthood there is nothing but what is spiritual. It hence appears, that the former was evanescent and temporary; but that the latter was to be perpetual.