Trinity

The Old Testament proclaimed the Father openly, and the Son more obscurely. The New manifested the Son, and suggested the deity of the Spirit. Now the Spirit Himself dwells among us, and supplies us with a clearer demonstration of Himself. For it was not safe, when the Godhead of the Father was not yet acknowledged, plainly to proclaim the Son; nor when that of the Son was not yet received to burden us further (if I may use so bold an expression) with the Holy Ghost; lest perhaps people might, like men loaded with food beyond their strength, or presenting eyes as yet too weak to bear it to the sun’s light, risk the loss even of that which was within the reach of their powers.

What then is procession? Tell me what is the unbegottenness of the Father, and I will explain to you the physiology of the generation of the Son and the procession of the Spirit, and both of us will be frenzy-stricken for prying into the mystery of God. And who are we to do these things, we who cannot even see what lies at our feet, or number the sand of the sea, or the drops of rain, or the days of eternity, much less enter into the depths of God, and supply an account of that nature which is so unspeakable and transcending all words?

We, therefore, both know and confess that God is without beginning, without end, eternal and everlasting, uncreated, unchangeable, invariable, simple, uncompound, incorporeal, invisible, impalpable, uncircumscribed, infinite, incognisable, indefinable, incomprehensible, good, just, maker of all things created, almighty, all-ruling, all-surveying, of all overseer, sovereign, judge; and that God is One, that is to say, one essence; and that He is known, and has His being in three subsistences, in Father, I say, and Son and Holy Spirit.