Hebrews 7:11-14

11Now if perfection [a perfect fellowship between God and the worshiper] had been attained through the Levitical priesthood (for under it the people were given the Law) what further need was there for another and different kind of priest to arise, one in the manner of Melchizedek, rather than one appointed to the order of Aaron?

12For when there is a change in the priesthood, there is of necessity a change of the law [concerning the priesthood] as well.

13For the One of whom these things are said belonged [not to the priestly line of Levi but] to another tribe, from which no one has officiated or served at the altar.

14For it is evident that our Lord descended from [the tribe of] Judah, and Moses mentioned nothing about priests in connection with that tribe.