In relation to the hypostasis of God as the Absolute Subject, there is the trihypostatic personality, which in one personal consciousness of self unites all the modes of the personal principle: I, thou, he, we, and you; whereas a unihypostatic personality has all these modes except I outside itself, in other personalities, and is thus limited and conditioned by them in its being. Fully manifested and actualized, the personal principle, the hypostasis, is a trihypostatic personality, in which the personal unity is revealed in the reality of three hypostatic centers, or hypostases, in triunity. Triunity is the divine number, not three and not one, but precisely triunity, Trinity. … Therefore, the first thing one must say about the Divine Person is that, as trihypostatic, this Person is equally real in one hypostasis and in three hypostases, that this Person is the pre-eternally realized reciprocity of love that totally vanquishes personal isolation and identifies three in one, while itself existing by the real being of these personal centers.

The trihypostatic Divinity is one Person, … And the Divine Person lives, actualizing His life in His nature. The one trihypostatic Divine Person has His divine nature — that is the fundamental definition of the Church. The trihypostatic God has His one nature, and He has this nature both as the Divine triunity in its unicity and as each hypostasis in its being: not only is the Son "consubstantial" with the Father (which was precisely the subject of dispute in the Arian epoch) but the Holy Spirit is "consubstantial" with the Father and with the Son. …

Creation, which is thus a free act of the will, and not (like the shining forth of the divine energies) a natural outpouring, is an act proper to a God who is personal, to the Trinity whose common will belongs to the divine nature and operates according to the determination of thought.

1. The Image of the Holy Trinity. Just as each man is made according to the image of the Trinitarian God, so the Church as a whole is an icon of God the Trinity, reproducing on earth the mystery of unity in diversity. In the Trinity the three are one God, yet each is fully personal; in the Church a multitude of human persons are united in one, yet each preserves his personal diversity unimpaired. The mutual indwelling of the persons of the Trinity is paralleled by the coinherence of the members of the Church. In the Church there is no conflict between freedom and authority; in the Church there is unity, but no totalitarianism. When Orthodox apply the word ‘Catholic’ to the Church, they have in mind (among other things) this living miracle of the unity of many persons in one.

Jesus is born from the Virgin Mary because he is the divine Son of God, the Saviour of the world. It is the formal teaching of the Orthodox Church that Jesus is not a “mere man” like all other men. He is indeed a real man, a whole and perfectly complete man with a human mind, soul and body. But he is the man which the Son and Word of God has become. Thus, the Church formally confesses that Mary should properly be called Theotokos, which means literally “the one who gives birth to God.” For the one born of Mary is, as the Orthodox Church sings at Christmas: “… he who from all eternity is God.”

Jesus of Nazareth is God, or, more accurately, the divine Son of God in human flesh. He is a true man in every way. He was born. He grew up in obedience to his parents. He increased in wisdom and stature (Lk 2.51–52). He had a family life with “brethren” (Mk 3.31–34), who according to Orthodox doctrine were not children born of Mary who is confessed as “ever-virgin,” but were either cousins or children of Joseph.

On the other hand, there is another terrible error, and the other terrible error, usually called Modalism in technical theological terminology, is where people say: there is «one God Who is the Holy Trinity», there is «He Who Is the Trinity». And we Orthodox Christians, following scripture, and the creedal statements, and the liturgical prayers, can never say: there is «one God Who is the Holy Trinity». There is «one God Who is the Father». And this one God Who is the Father has with Him eternally, Whom He begets timelessly before all ages, His only-begotten Son — Who is also His Logos, His Word, and also His Chokhmah, His Sophia, His Wisdom, also His Eikona, His Ikon, His Image. But this Wisdom and Word and Image and Ikon of God is divine with the very same divinity as God, the One True and Living God, because «He is Who He is», and His is another Who from the Father. There are three Whos. There is He Who is the Father, He Who is the Son, and He Who is the Holy Spirit. Those three Whos are called the three Persons or three Hypostases. Probably the term «hypostases» is a better term, because it means three instances of divine life in a perfect and total unity. But it is important to remember that the one God is the Father of Jesus. Jesus is the Son of God. As the Nicene Creed said, “He is God from God, true God from true God”. Here the Christians would say and insist that the one God and Father, from all eternity, has with Him His Son.

First of all, it is the Church’s teaching and its deepest experience that there is only one God because there is only one Father.

In the Bible the term “God” with very few exceptions is used primarily as a name for the Father. Thus, the Son is the “Son of God,” and the Spirit is the “Spirit of God.” The Son is born from the Father, and the Spirit proceeds from the Father — both in the same timeless and eternal action of the Father’s own being.

In this view, the Son and the Spirit are both one with God and in no way separated from Him. Thus, the Divine Unity consists of the Father, with His Son and His Spirit distinct from Himself and yet perfectly united together in Him.