This verse connects itself with the parenthesis in Hebrews 7:11. “For if the priesthood is changed there takes place also of necessity a change of law.” It is no light matter to speak of the order of Aaron as set aside: this carries with it a change of law.
Related Commentaries of Hebrews 7:12
Hebrews 7:12
12 For the priesthood being changed, there is made of necessity a change also of the law.