A.T. Robertson Commentary Hebrews 7:16

"who hath been made, not after the law of a carnal commandment, but after the power of an endless life:" — Hebrews 7:16 (ASV)

Carnal (σαρκινης). "Fleshen" as in 1 Corinthians 3:1, not σαρκικης (fleshlike, 1 Corinthians 3:3). The Levitical priests became so merely by birth.

Of an endless life (ζωης ακαταλυτου). Late compound (alpha privative and verbal adjective from καταλυω, to dissolve, as in 2 Corinthians 4:1), indissoluble. Jesus as priest lives on forever. He is Life.