Hebrews 7:4-6

7:4 But see how great he must be, if Abraham the patriarch gave him a tithe of his plunder. 7:5 And those of the sons of Levi who receive the priestly office have authorization according to the law to collect a tithe from the people, that is, from their fellow countrymen, although they too are descendants of Abraham. 7:6 But Melchizedek who does not share their ancestry collected a tithe from Abraham and blessed the one who possessed the promise.

Hebrews 7:9-12

7:9 And it could be said that Levi himself, who receives tithes, paid a tithe through Abraham. 7:10 For he was still in his ancestor Abraham’s loins when Melchizedek met him.

Jesus and the Priesthood of Melchizedek

7:11 So if perfection had in fact been possible through the Levitical priesthood – for on that basis the people received the law – what further need would there have been for another priest to arise, said to be in the order of Melchizedek and not in Aaron’s order? 7:12 For when the priesthood changes, a change in the law must come as well.