Although in Christian verity we ought to acknowledge each Person as God and Lord, yet by Christian faith it is not allowable to affirm or to name three Gods or three Lords.
This can only mean that we ought to acknowledge three Gods and Lords, but it is not allowable to affirm or name three Gods and three Lords.
[2] Who can possibly have a perception of one God unless He is one in person? If it is said that such a concept is possible if one thinks of the three as having one essence, does one, indeed can one, have any other idea than that they are thus of one mind and agree, and yet are three Gods? Thinking more deeply, one asks oneself, How can the divine essence, which is infinite, be divided? Further, how can divine essence from eternity beget another and produce still another who proceeds from them both? It may be said that it is to be believed and not thought about; but who does not think about what he is told must be believed? How else can there be any acknowledgment which in its essence is faith? Was it not because of the concept of God as three persons that Socinianism and Arianism arose, which prevail in the hearts of more persons than you suppose? Belief in one God and that this God is the Lord makes the church, for in Him is the divine trinity. The truth of this may be seen in Doctrine of the New Jerusalem about the Lord, from beginning to end.
[3] But what is thought of the Lord today? Is it not thought that He is God and Man, God from Jehovah the Father of whom He was conceived and Man from the Virgin Mary from whom He was born? Who thinks that God and Man in Him, or His Divine and His Human, are one person, and are one as soul and body are? Does anyone know this? Ask the learned in the church and they will say that they have not known it. Yet it is part of the doctrine of the church received throughout Christendom, as follows:
Our Lord Jesus Christ, the Son of God, is God and Man; and although He is God and Man yet there are not two, but there is one Christ. He is one because the divine took to itself the human; indeed He is altogether one, for He is one Person, since as soul and body make one man, so God and Man is one Christ.
This comes from the Faith or Creed of Athanasius. The learned have not known it because on reading this they have thought of the Lord not as God but only as Man.
[4] When they are asked if they know from whom the Lord was conceived, whether from God the Father or from His own Divine, they reply that He was conceived from God the Father, for this is according to Scripture. Are the Father and He not one then, like soul and body? Who can think that He was conceived from two Divines, and if from His own that this was His Father? If you ask them further what their idea of the Lord's Divine and of His Human is, they will say that His Divine is from the essence of the Father and His Human from the essence of His mother, and that His Divine is with the Father. Then, when they are asked where His Human is, they have no answer, for they separate His Divine and His Human in their thinking and make His Divine equal to the Divine of the Father and His Human like the human of another man, unaware that in doing this they separate soul and body; nor do they see the flaw in this, that then a rational man would have been born from a mother alone.
[5] As a result of the fixed idea that the Lord's humanity was like that of another man, it has come about that a Christian can with difficulty be led to think of a Divine Human, even when it is said that the Lord's soul or life from conception was and is Jehovah Himself. Now sum up the reasons and consider whether there is any other God of the universe than the Lord alone, in whom is the Divine itself, Source of all, called the Father; the Divine Human, called the Son; and the proceeding Divine, called the Holy Spirit; and thus that God is one in person and essence, and that this God is the Lord.
[6] You may persist and remark that the Lord Himself spoke of three in Matthew:
Go and make disciples of all nations, baptizing them in the name of the
Father, the Son and the Holy Spirit (28:19).