Theological glossary · FaithLogic

Ousia (essence / substance / being)

What something is — the divine nature that Father, Son, and Spirit each fully possess.

Greek ousia, from einai, 'to be'; Latin substantia or essentia.

Not a biblical term; the concept answers 'what is God?' as against 'who is God?'

Fixed at Nicaea in homoousios and at Constantinople in 'one ousia, three hypostaseis'. Early on ousia and hypostasis were near-synonyms, which caused confusion the Cappadocians resolved.

There is one, undivided divine ousia; the persons are not three parts or three instances of it but each the whole.

Largely agreed across Chalcedonian traditions; the philosophical framing is debated (e.g. how it relates to divine simplicity).

Open in the glossary for related terms and the doctrines this concept appears in.