Hebrews 7:4-10

You realize just how great Melchizedek is when you see that Father Abraham gave him a tenth of the captured treasure. Priests descended from Levi are commanded by law to collect tithes from the people, even though they are all more or less equals, priests and people, having a common father in Abraham. But this man, a complete outsider, collected tithes from Abraham and blessed him, the one to whom the promises had been given. In acts of blessing, the lesser is blessed by the greater. Or look at it this way: We pay our tithes to priests who die, but Abraham paid tithes to a priest who, the Scripture says, “lives.” Ultimately you could even say that since Levi descended from Abraham, who paid tithes to Melchizedek, when we pay tithes to the priestly tribe of Levi they end up with Melchizedek.