World Wide Study Bible
a Bible passage
12. For—the reason why Paul presses the words "after the order of Melchisedec" in Ps 110:4, namely, because these presuppose a change or transference of the priesthood, and this carries with it a change also of the law (which is inseparably bound up with the priesthood, both stand and fall together, Heb 7:11). This is his answer to those who might object, What need was there of a new covenant?