Hebrews 7:15-17 - Joseph Benson’s Commentary on the Old and New Testaments

And it is yet far more evident That both the priesthood and the law are changed, because the priest now raised up is not only of another tribe, and of a quite different order, but is made a priest; not after the law of a carnal commandment With such carnal rites and outward solemnities as the law prescribed for those priests, which reached no further than to the purifying of the flesh; but after the power of an endless life Which he has in himself as the eternal Son of God. Being a sacrifice, as well as a priest, it was indeed necessary that he, as a man, should die; but as he continued only a short while in the state of the dead, and arose to die no more, he may justly be said to have an endless life, even as to his human nature. Besides, it should be considered that his life, as a priest, did not begin till after his ascension, when he passed through the heavens into the holiest of all, with the sacrifice of his crucified body. And having offered that body there, he sat down at the right hand of the throne of his Father's majesty, where he remains the minister of that true tabernacle, making continual intercession for his people.