The Triune God, Father, Son and Holy Spirit:
We confess with the ancient Christian Church the Athanasian Creed without reservation: “Whosoever will be saved, before all things, it is necessary that he hold the catholic (i.e., universal, Christian) faith.
“Which faith except everyone do keep whole and undefiled, without doubt he shall perish everlastingly.
“And the catholic faith is this, that we worship one God in Trinity and Trinity in Unity.”
The Bible makes it clear that the one true God consists of three distinct persons. While the Trinity is not as clearly revealed in the Old Testament as in the New Testament, there are definite indications in the Old Testament of three distinct persons in the Godhead. The Trinity is not a doctrine which was fabricated by the early church, but it is a divinely revealed truth.29
29 Matthew 28:19. Otten, ep. cit., pp. 11-13.
The Sixteenth Century Reformers did not modify the doctrine of the Holy Trinity in any manner. Article l of the Augsburg Confession declares:
Our churches, with common consent, do teach that the decree of the Council of Nicaea concerning the Unity of the Divine Essence and concerning the Three Persons, is true and to be believed without any doubting; that is to say, there is one Divine Essence which is called and which is God; eternal, without body, without parts, of infinite power, wisdom, and goodness, the Maker and Preserver of all things, visible and invisible; and yet there are three Persons, of the same essence and power, who also are coeternal, the Father, the Son, and the Holy Ghost. And the term "person" they use as the Fathers have used it, to signify, not a part or quality in another, but that which subsists of itself.
They condemn all heresies which have sprung up against this article, as the Manichaeans, who assumed two principles, one Good and the other Evil; also the
Valentinians, Arians, Eunomians, Mohammedans, and all such. They condemn also the Samosatenes, old and new, who, contending that there is but one Person, sophistically and impiously argue that the Word and the Holy Ghost are not distinct Persons, but that "Word" signifies a spoken word, and "Spirit" signifies motion created in things.