vid. ad Afros. 5, 6. ad Serap. ii. 5. S. Ambrose tells us, that a Letter written by Eusebius of Nicomedia, in which he said, ‘If we call Him true Son of the Father and uncreate, then are we granting that He is one in essence, ὁμοούσιον,’ determined the Council on the adoption of the term. de Fid. iii. n. 125. He had disclaimed ‘of the essence,’ in his Letter to Paulinus. Theod. Hist. i. 4. Arius, however, had disclaimed ὁμοούσιον already, Epiph. Hær. 69. 7. It was a word of old usage in the Church, as Eusebius of Cæsarea confesses in his Letter, infr. Tertullian in Prax. 13 fin. has the translation ‘unius substantiæ:’ (vid. Lucifer de non Parc. p. 218.) as he has ‘de substantia Patris,’ in Prax. 4. and Origen perhaps used the word, vid. Pamph. Apol. 5. and Theognostus and the two Dionysii, infr. §25, 26. And before them Clement had spoken of the ἕνωσις τῆς μοναδικῆς οὐσίας, ‘the union of the single essence,’ vid. Le Quien in Damasc. Fid. Orth. i. 8. Novatian too has ‘per substantiæ communionem,’ de Trinit. 31.