Gennadius of Massalia on the Holy Trinity

 "We believe (there) to be One God, the Father and the Son and the Holy Ghost: the Father Him Which has the Son, the Son Him Which has the Father, the Holy Ghost Him Which is from the Father Proceeding, Co-Eternal to the Father and the Son.  The Father therefore is the Origin of Divinity, Who just as at no time was not God thus at no time was not the Father; from Whom the Son is Begotten; from Whom the Holy Ghost, not Begotten (for He is not the Son) neither Unbegotten (for He is not the Father), nor made, but from God the Father Proceeding.  The Father Eternal, Him that has the Eternal Son is that which is the Eternal Father; the Eternal Son, Him that is Co-Eternal to the Father; the Eternal Holy Ghost, Him that is Co-Eternal to the Father and Son: not a confused Trinity in one person, as Sabellius says, neither a Divinity separated or divided in nature, as Arius blasphemed, but the Father in one Person, the Son in another Person, and the Holy Ghost in a Third Person, One Nature in the Holy Trinity, God, Father and Son and Holy Ghost.”

[Gennadius, Presbyter of Marseille (+496), Chapter 1,  Liber Sive DefinitioEcclesiasticorum Dogmatum]

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