Theological glossary · FaithLogic
Homoousios (of one substance)
The Nicene word: the Son is of the very same being as the Father, not merely similar.
Greek homos ('same') + ousia ('being').
Not biblical; adopted precisely because Scripture's language (John 10:30; Col 2:9; Heb 1:3) could be evaded by Arius while its sense could not.
Suspect before Nicaea (used earlier by some Gnostics and by Paul of Samosata in a modalist sense), it was chosen at Nicaea as the one term Arius could not accept. Defended for fifty years by Athanasius; confirmed 381.
Rules out the Son being a creature or a lesser divinity; secures that to meet the Son is to meet God.
Universal among Nicene Christians; rejected by Arians and modern subordinationists.
Open in the glossary for related terms and the doctrines this concept appears in.