There is one God, the Father of the living Word, who is the substantive wisdom and eternal power and image of God: the perfect origin (begetter) of the perfect (begotten): the Father of the only-begotten Son.
There is one Lord, one of one (only of the only), God of God, the image and likeness of the Godhead, the mighty Word, the wisdom which comprehends the constitution of all things, and the power which produces all creation; the true Son of the true Father, Invisible of Invisible, and Incorruptible of Incorruptible, and Immortal of Immortal, and Everlasting of Everlasting.
And there is one Holy Ghost, having his existence from God, and being manifested by the Son, namely, to men, the perfect likeness of the perfect Son, Life, the cause of the living, Sacred Fount, Sanctity, the Leader of sanctification: in whom is revealed God the Father, who is over all things and in all things, and God the Son, who is through all things: a perfect Trinity, not divided nor differing in glory and eternity and sovereignty.
Neither, indeed, is there any thing created or subservient in the Trinity, nor introduced, as though not there before but coming in afterwards; nor, indeed, has the Son ever been without the Father, nor the Spirit without the Son, but the Trinity is ever the same, unvarying and unchangeable. (Philip Schaff, Creeds of Christendom)