How do we understand the inter-Trinitarian relations? Huh? What does that question even mean?! In other words, how do the persons of the Trinity relate to each other? This is not an unimportant question, because the answers we give to this question will affect what we think about the incarnation of our Lord. Who is it that in the manger lies? We can only answer that question when we know who He is in relation to His Father and the Spirit. We, of course, stand on the shoulders of giants; the ancient church's faithful defenders of the Trinitarian faith, such as Athanasius, the Cappadocians, Cyril of Alexandria, and others. They drew out from the Holy Scripture the implications of the Trinitarian teaching, clarifying only what was quite clearly there when they were forced to do so by the enemies of the truth. Only when the opponents of the truth of the Trinity rejected that truth did men like Athanasius seek to make clear the article of the holy Trinity for the people of their time. Their efforts bore fruit in the various ecumenical statements of the faith, which arose beginning in 325 with the Nicene Symbol.

 

One of those groups whose teaching demanded a clear reply were the Sabellians, who taught that the godhead was a single person that changed in mode rather than subsisting in three persons. In Sabellianism, it is as though God were a Transformer, like the child's toy and movie character: Father changing into Son, changing into Spirit. This heresy was also called modalism; in which God simply changes in mode to become Father, Son, or Holy Spirit. This was an attempt to maintain the oneness of God; unfortunately at the cost of denying the three persons of the Trinity. Sabellianism also implied that the Father died as well as the Son, because Son is only a mask or mode of God. For this reason the ancient church also called Sabellianism "patripassionism," which means "the-Father-suffered-ism." If the Son is merely a mode of God, then indeed the Father must have died when the Son died. The Cappadocians especially argued that the internal relations of the Trinity were not equal and were "divided." The Father does not die, only the Son. Who is it then, who in the manager lies: He is God of God, the Creator of all that is. He has existed in the bosom of His Father from eternity ( Jn 1:18). He is begotten without beginning and without end from His Father as God from God. He does not beget the Father, but is begotten of Him. This Child born of Mary is none other than God of God, and yet a subsisting individual.

 

A related question is 'How do the persons of the Trinity relate to us?' The persons of the Trinity relate to us in an undivided manner; that is that they, all three persons, work together in all they do to accomplish our salvation. What theologians have called the external relations of the Trinity are undivided. This means that the will of God the Father to save the world in His Son, and to share that salvation in the work of the Holy Spirit, is really a single divine will, not subject to any kind of partition or division. It was the eternal God's united will toward us that Christ should bear our flesh of the Virgin and bearing us in that flesh, die in our place. It does matter that you think thus about the Trinity (Athanasian Creed, 26).