Homoousios (Consubstantial)

Of one essence: the word the First Ecumenical Council put into the Creed to say that the Son is God in exactly the sense the Father is, not a lesser god and not the first of creatures. It was a hard word to choose. It is not in Scripture, and it had been used in a sense condemned at Antioch in 268, and for half a century after Nicaea bishops who were not Arians preferred homoiousios, of like essence, a single letter away. St Athanasius held that nothing less would do, and the Cappadocians won over those who had hesitated by showing that one essence need not mean one person. The Second Council confirmed it in 381. Chalcedon then used the same word twice: Christ is of one essence with the Father in His divinity and of one essence with us in His humanity.