It should be added that the Father, the Son, and the Holy Spirit are not common names, but each Person has its own Name. The Father is not called the Son, and the Son is not called the Father, and the Holy Spirit is not called either the Father or the Son. God is always called the Trinity; although He has three Hypostases and three Persons, He is one Being, one Essence, one Godhead, one Wisdom, one power and one will. And there was not one Hypostasis before the time, and the other after: the Father, the Son, and the Holy Spirit are inseparable; The faces of God are not separated from each other by years, nor by disposition, nor by will, nor by intention, nor by action, nor by passion — none of the things that we see in people. Therefore God is one: not three Gods, but one in three Hypostases, that is, Persons. And nothing of the Divine Trinity was earlier or later than the other, there was neither growing nor decreasing, nothing began or ended.

And the first great true light is God the Father, unbegotten, incorruptible, invisible, incorporeal, indescribable, ineffable, incomprehensible, the Creator of Heaven and earth, of all things visible and invisible. And the Son is light, as He Himself said: "I am the light of the world" (John 8:12). The true light is from the true Light, the true God is from the true God, the likeness and image of God, the active Word, the Wisdom that contains all, the Hypostasis and power that creates all creation, the One through Whom all things came into existence, and all that the Father has belongs to the Son, as He Himself said: "All that the Father has is Mine" (John 16:15), and "He who has seen Me has seen the Father" (John 14:14). 9.) — and: "I am in the Father, and the Father in Me" (John 14:10), — for He was born of the Father before all ages, ineffable, ineffable, incomprehensible, without passion, without combination, without confusion, incorporeal, out of time, like rays from the sun, like a flame from a fire, like a channel from a river. And not like those who are born, who can no longer be in those who begat them, but as a ray that proceeds from the sun and abides in the sun, enlightening the world and not parting from the sun; and as flame and light, proceeding from fire, giving men sensual light, and abiding in the fire; and like a channel branching off from the river, watering people and not parting from the river. The Word, eternally abiding in the Father and from the Father and with the Father, inseparable, inseparable, unchanging.

Having spoken briefly about the Divine Nature of Christ, let us say a little about His human Nature, which He assumed for the sake of our salvation. For being God, He became, for our sake, also a perfect Man, He became in the last days, He was born of the Holy Virgin Mother of God Mary, the great, pre-eternal, beginningless, invisible, incomprehensible and indescribable, knowing the hearts of all people. There are, therefore, two of His births. The first is from the Father, pre-eternal, timeless, incorporeal: He shone like the light from the sun. The second is from the Holy Virgin Mary, seedless from the Holy Spirit. Therefore He is known in two natures, the Divine and the human. And He has one Hypostasis, for He is one, the Son of God and the Son of the Virgin. He is both God and Man, in two natures: for He is of one essence with the Father in Divinity and of one essence with the Mother in humanity. And there are two actions in it – Divine and human, and two wills, that is, desires. Thus, having the Divine will, He, as God, created the Divine by it, raising the dead, giving sight to the blind, and working many other unspeakable signs and wonders. But He also had a human will, or desire; for He took on human flesh and spiritual actions and passions, in order to show the true incarnation, and not a vision, sweeping aside the evil passions that defile our lives as unworthy of the Most-Pure Divinity. He suffered, having two Natures: for in the Flesh He hung on the Cross, in the Flesh He suffered, in the Flesh He died, while His Divinity remained impassible.

And He appeared to the disciples in the already incorruptible and deified Flesh, after the resurrection, and ascended to heaven with the Flesh, and sat down at the right hand of the Father in the deified Flesh, and not in corruptible decay, as we do. And He will come again in glory to judge the living and the dead, and His kingdom has no end.

But the Light and the Holy Spirit, the true and life-giving God, is perfect and of one essence with the Father and the Son, omnipotent, omnipotent, sanctifies all, dominates, possesses, reigns, dominates, has no beginning, invisible, incomprehensible, unexplored, ineffable, Who created with the Father and the Son a rational and sensual creature, proceeding from the Father, — but not from the Son, as the Latin heretics assert in their wisdom.

Who testifies that the Holy Spirit proceeds from the Father and not from the Son? — The Truth Itself, our Lord Jesus Christ. For He said: "When the Comforter comes, Whom I will send you from the Father, the Spirit of truth, Who proceeds from the Father" (John 15:26. And again He says, "If you love Me, keep My commandments. And I will pray the Father, and He will give you another Comforter, that He may be with you forever, the Spirit of truth" (John 14:15-17). And again, "These things have I said to you while I was with you. But the Comforter, the Holy Spirit, whom the Father will send in My name, will teach you all things" (John 14:25-26).

You see, He nowhere says, "The Holy Spirit proceeds from the Father and from Me"! And what is truer than this testimony? Answer us to this! And if Christ is the Word of God and is called God's Wisdom and Truth, and knows everything as God, then who can say that He spoke falsely? Only the one who does not confess that our Lord Jesus Christ is the true God. But if anyone calls Him the true God, he confesses that what He says is true.

Heretics assert that Christ said this as a humble Man, according to human nature, for Christ said many things about Himself humbly, in a human way, as: "Seek ye to kill Me, the Man" (John 8:40). He said this as a Man. And there is much of this in the Holy Gospel. Christ spoke both humbly, as a Man, and with authority, as God. It is precisely because of human humility, the heretics assert, that Christ also said that the Holy Spirit proceeds from the Father, but did not attribute this to Himself.

But these are false heretical teachings! When the Lord said, "Whom I will send to you," He said this to His disciples, not as a man, but precisely as God: for man does not send God. Since the Holy Spirit is God, the Lord also says as God: "Whom I will send to you." And not once, but many times, He said that the Spirit proceeds from the Father in order to stop the mouths of those who wish to assert that the Holy Spirit proceeds from the Son.

Some point out that Christ, having breathed, said to His disciples: "Receive ye the Holy Spirit" (cf. John 20:22), and therefore they believe that the Holy Spirit proceeds from the Son.

To this Athanasius the Great answers: It should be known that when Christ, having breathed, said to His disciples: "Receive the Holy Spirit," He did not give them the Essence of the Holy Spirit, but a spiritual gift, as He Himself testifies, saying: "It is better for you that I should go; for if I do not go, the Comforter will not come to you" (John 16:7). It is obvious that if Christ has not yet departed, then this breath was not the coming of the Comforter, but a gift of spiritual grace. And when He said, "Receive ye the Holy Spirit," He added, "To whom ye forgive sins, they shall be forgiven; on whom ye shall retain, they shall remain" (John 20:23). From this it is clearly seen that this breath was a spiritual gift to forsake and forgive sins, and not the Hypostasis and Essence of the Holy Spirit; for it is customary for the Scriptures to call a spiritual gift a spirit, as Isaiah writes of Christ: "A sprout shall come forth from the root of Jesse, and a branch shall sprout from his root," and seven spirits shall rest upon it, that is, the seven spiritual gifts. And so that no one would ponder what these seven spirits are, he himself interpreted them as "the spirit of wisdom and understanding, the spirit of counsel and strength, the spirit of knowledge and godliness" (Isaiah 11:1-2), "the spirit of the fear of God" (See Isaiah 11:3, in the Synodal translation — "and he shall be filled with the fear of the Lord"). And Gregory the Theologian says: it is convenient for Isaiah to call actions, I mean spiritual, spirits, because the spiritual nature itself is not divided, but divides the gifts.

When He ascended to Heaven, the disciples received the Holy Spirit as a Hypostasis. For the Lord Himself says of this: "Ye shall receive power, when the Holy Spirit shall come upon you" (Acts 1:8). As it happened on the day of Pentecost, of which the Apostle Peter also testifies, that the apostles then received the Holy Spirit – on the day of Pentecost. He says, "This Jesus God hath raised up... Therefore He, having been lifted up by the right hand of God, and having received from the Father the promise of the Holy Spirit, poured out that which ye now see and hear" (Acts 2:32-33), and this was on the day of Pentecost, and not when Christ breathed.

Thus testifies the Lord our God Himself, Jesus Christ; and the great Apostle Peter also says that the Holy Spirit proceeds from the Father, and not from the Son, and that the Holy Spirit came on the day of Pentecost, and not when Christ breathed on the disciples.

And the seven Ecumenical Councils, in which two thousand holy fathers participated, and the most sacred holy local councils, at which a multitude of great God-bearing fathers and wonderworkers gathered, all confirm the confession of the Orthodox faith in the Holy Spirit, true, life-giving, proceeding from the Father; but no one says that He proceeds from the Son.