And I saw (see on Revelation 5:1). A strong angel; ἰσχυρόν, rendered "mighty" in Revelation 10:1. Possibly, as De Wette and others think, so called because of higher rank—De Lyra says Gabriel; but probably on account of the great voice, which sounded "as a lion roareth" (Revelation 10:3).
Proclaiming with a loud voice, Who is worthy to open the book, and to loose the seals thereof? with a great voice. "Worthy" is ἄξιος, fit morally, as in John 1:27.