A.T. Robertson Commentary Ephesians 1:19

"and what the exceeding greatness of his power to us-ward who believe, according to that working of the strength of his might" — Ephesians 1:19 (ASV)

The exceeding greatness of his power (το υπερβαλλον μεγεθος της δυναμεως αυτου). Μεγεθος is an old word (from μεγας), but here only in N.T. Hυπερβαλλον, present active participle of υπερβαλλω, reappears in 2:7; 3:19 and seen already in 2 Corinthians 3:10; 9:14. To enlightened eyes the greatness of God's power is even more "surpassing."