Origen, in the Catena on St. John iii. 8:  “This also shews that the Spirit is a Being (οὐσίαν):  for He is not, as some suppose, an energy of God, having according to them no individuality of subsistence.  And the Apostle also, after enumerating the gifts of the Spirit, immediately added, But all these worketh the one and the same Spirit, dividing to each one severally as He will.  Now if He willeth and worketh and divideth, He is surely an energizing Being, but not an energy” (Suicer, Thesaurus, Πνευμα).