He advances reasons to show not only that the Father is not greater than the Son, but that neither are both together anything greater than the Holy Spirit, nor any two together in the same Trinity anything greater than one, nor all three together anything greater than each singly. He also intimates that the nature of God may be understood from our understanding of truth, from our knowledge of the supreme good, and from our implanted love of righteousness; but above all, that our knowledge of God is to be sought through love, in which he notices a trio of things which contains a trace of the Trinity.
Doctrinal Treatises (On the Trinity, Enchiridion, On the Catechizing of the Uninstructed, On Faith and the Creed, etc.) · Saint Augustine of Hippo
Explains and proves that not only the Father is not greater than the Son, but neither are both together anything greater than the Holy Spirit, nor any two together in the same trinity anything greater than one, nor all three together anything greater than each severally. It is then shown how the nature itself of God may be understood from our understanding of truth, and from our knowledge of the supreme good, and from the innate love of righteousness, whereby a righteous soul is loved even by a soul that is itself not yet righteous. But it is urged above all, that the knowledge of God is to be sought by love, which God is said to be in the Scriptures; and in this love is also pointed out the existence of some trace of a trinity.
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