The Christian truth of the oneness of God is deepened by the truth of the Tri-hypostatical unity.

2. The dogma of the Holy Trinity

God is one in Essence and Triple in Persons. The dogma of the Trinity is the second fundamental dogma of Christianity. A whole series of the Church's great dogmas are founded immediately upon it, beginning first of all with the dogma of our Redemption. Because of its special importance, the doctrine of the All-Holy Trinity constitutes the content of all the Symbols of Faith which have been and are now used in the Orthodox Church, as well as all the private confessions of faith written on various occasions by the shepherds of the Church.

Because the dogma of the All-Holy Trinity is the most important of all Christian dogmas, it is the most difficult for the limited human mind to grasp. This is why no battle in the history of the ancient Church was as intense as that over this dogma and the truths that are immediately bound up with it.

The dogma of the Holy Trinity includes in itself two fundamental truths:

1. God is one in Essence, but triple in Person. In other words, God is a Tri-unity, is Tri-hypostatical, is a Trinity One in Essence.
2. The Hypostases have personal or hypostatic attributes: God is unbegotten; the Son is begotten from the Father; the Holy Spirit proceeds from the Father.

We worship the All-Holy Trinity with a single and inseparable worship. In the Church Fathers and the Divine services, the Trinity is often called a Unity in Trinity, a Tri-hypostatical Unity. In most cases, prayers addressed to one person of the Holy Trinity end with a glorification or doxology to all Three Persons (for example, in a Prayer to the Lord Jesus Christ: "For most glorious art Thou, together with Thine unoriginate Father, and the All-Holy Spirit, unto the ages. Amen").

The Church, addressing the All-Holy Trinity in prayer, invokes It in the singular, not the plural, number. For example, "For Thee" (and not "you") "all the heavenly powers praise, and to Thee (not "to you") we send up glory, to the Father, to the Son and to the Holy Spirit, now and ever and unto the ages of ages. Amen."

Acknowledging the mystical nature of this dogma, the Church of Christ sees in it a great revelation that exalts the Christian faith incomparably above any confession of simple monotheism, such as may be found in non-Christian religions. The dogma of the Three Persons indicates the fullness of the mystical inward life in God, for God is love and the love of God cannot merely be extended to the world created by Him: in the Holy Trinity this love is directed within the Divine Life also. The dogma of the Three Persons indicates even more clearly for us the closeness of God to the world: God above us, God with us, God in us and in all creation.

Above us is God the Father, the ever-flowing Source, as it is expressed in the Church's prayer, the Foundation of all being, the Father of mercies Who loves and cares for us, His creation, for we are His children by grace.

With us is God the Son, begotten by Him, Who for the sake of Divine love has manifested Himself to men as Man so that we might know and see with our own eyes that God is with us most intimately, partaker of flesh and blood with us (Heb. 2:14) in the most perfect way.

In us and in all creation — by His power and grace — is the Holy Spirit, Who fills all things, is the Giver of Life, Life-creator, Comforter, Treasury and Source of good things. Having an eternal and pre-eternal existence, the Three Divine Persons were manifested to the world with the coming and Incarnation of the Son of God, being "one Power, one Essence, one Godhead" (Stichera for Pentecost, Glory on "Lord, I have cried").

Because God in His very Essence is wholly consciousness, thought, and self-awareness, each of these three eternal manifestations of Himself by the one God has self-awareness, and therefore each one is a Person. In addition, these Persons are not simply forms or isolated manifestations or attributes or activities; rather, the Three Persons are contained in the very Unity of God's Essence. Thus, when in Christian doctrine we speak of the Tri-unity of God, we speak of the mystical inward life hidden in the depths of the Divinity, revealed to the world in time, in the New Testament, by the sending down of the Son of God from the Father into the world and by the activity of the wonderworking, life-giving, saving power of the Comforter, the Holy Spirit.