Hebrews 7:5-9

5And 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.

6But Melchizedek who does not share their ancestry collected a tithe from Abraham and blessed the one who possessed the promise.

7Now without dispute the inferior is blessed by the superior,

8and in one case tithes are received by mortal men, while in the other by him who is affirmed to be alive.

9And it could be said that Levi himself, who receives tithes, paid a tithe through Abraham.