Joseph Benson's Commentary of the Old and New Testaments - Hebrews 7:12-14
Hebrews 7:12-14. For, or, wherefore, the priesthood On account of which the law was given; being changed, of necessity there must be a change also of the law As if he had said, Since there is such a near relation between the priesthood and the law, and since the whole administration of the law, as the rule of worship, depended absolutely on the Aaronical priesthood, therefore the one being changed, the other must be changed also. “Under the law the offices of the priesthood consisted... read more
Albert Barnes' Notes on the Whole Bible - Hebrews 7:12
For the priesthood being changed - According to the prediction in Ps. cx., that it would be. When that occurs, the consequence specified will also follow.There is made of necessity a change also of the law - The Law so far as it grew out of that, or was dependent on it. The connection requires us to understand it only of the Law “so far as it was connected with the Levitical priesthood.” This could not apply to the ten commandments - for they were given before the institution of the priesthood;... read more