3 Without father or mother, without genealogy, without beginning of days or end of life, resembling the Son of God, he remains a priest forever.
4 Just think how great he was: Even the patriarch Abraham gave him a tenth of the plunder!
5 Now the law requires the descendants of Levi who become priests to collect a tenth from the people—that is, from their fellow Israelites—even though they also are descended from Abraham.
6 This man, however, did not trace his descent from Levi, yet he collected a tenth from Abraham and blessed him who had the promises.
7 And without doubt the lesser is blessed by the greater.
8 In the one case, the tenth is collected by people who die; but in the other case, by him who is declared to be living.
9 One might even say that Levi, who collects the tenth, paid the tenth through Abraham,
10 because when Melchizedek met Abraham, Levi was still in the body of his ancestor.

Jesus Like Melchizedek

11 If perfection could have been attained through the Levitical priesthood—and indeed the law given to the people established that priesthood—why was there still need for another priest to come, one in the order of Melchizedek, not in the order of Aaron?
12 For when the priesthood is changed, the law must be changed also.
13 He of whom these things are said belonged to a different tribe, and no one from that tribe has ever served at the altar.