Hebrews 7:3, 8, 23-25

Without father, without mother, without genealogy, having neither beginning of days nor end of life, but made like the Son of God, he remains a priest perpetually.

In this case mortal men receive tithes, but in that case one receives them, of whom it is witnessed that he lives on.

The former priests, on the one hand, existed in greater numbers because they were prevented by death from continuing, but Jesus, on the other hand, because He continues forever, holds His priesthood permanently. Therefore He is able also to save forever those who draw near to God through Him, since He always lives to make intercession for them.