Hebrews 7:1-7

ASV(i) 1 For this Melchizedek, king of Salem, priest of God Most High, who met Abraham returning from the slaughter of the kings and blessed him, 2 to whom also Abraham divided a tenth part of all (being first, by interpretation, King of righteousness, and then also King of Salem, which is, King of peace; 3 without father, without mother, without genealogy, having neither beginning of days nor end of life, but made like unto the Son of God), abideth a priest continually.
4 Now consider how great this man was, unto whom Abraham, the patriarch, gave a tenth out of the chief spoils. 5 And they indeed of the sons of Levi that receive the priest's office have commandment to take tithes of the people according to the law, that is, of their brethren, though these have come out of the loins of Abraham: 6 but he whose genealogy is not counted from them hath taken tithes of Abraham, and hath blessed him that hath the promises. 7 But without any dispute the less is blessed of the better.