A.T. Robertson Commentary Hebrews 7:8

"And here men that die receive tithes; but there one, of whom it is witnessed that he liveth." — Hebrews 7:8 (ASV)

Here (ωδε). In the Levitical system.

There (εκε). In the case of Melchizedek.

Of whom it is witnessed (μαρτυρουμενος). "Being witnessed," present passive participle of μαρτυρεω (personal construction, not impersonal).

That he lives (οτ ζη). Present active indicative of ζαω). The Genesis record tells nothing of his death.