40 Thrust out now your quivering and hissing tongues, you vipers of heresy, whether it be thou Sabellius or thou Photinus, or ye who now preach that the Only-begotten God is a creature. Whosoever denies the Son shall hear of one God the Father, because inasmuch as a father becomes a father only by having a son, this name Father necessarily connotes the existence of the Son. And again, let him who takes away from the Son the unity of an identical nature, acknowledge one Lord Jesus Christ.
For unless through unity of the Spirit He is one Lord room will not be left for God the Father to be Lord. Again, let him who holds the Son to have become Son in time and by His Incarnation, learn that through Him are all things and we through Him, and that His timeless Infinity was creating all things before time was. And meanwhile let him read again that there is one hope of our calling, and one baptism, and one faith; if, after that, he oppose himself to the preaching of the Apostle, he, being accursed because he framed strange doctrines of his own device, is neither called nor baptized nor believing; because in one God the Father and in one Lord Jesus Christ there lies the one faith of one hope and baptism.
And no alien doctrine can boast that it has a place among the truths which belong to one God and Lord and hope and baptism and faith.
Source: On the Trinity (New Advent)