The Spirit of God is also light, having the source of the Father, from Whom it proceeds. Germanus, Patriarch of Constantinople: He who says that the Holy Spirit proceeds also from the Son, and says that the Son is the beginning of the existence of the Holy Spirit, like the Father, is worthy of condemnation and goes into perdition, because he belittles the Holy Spirit and destroys His honor. Someone may say to this: The Son proceeds from the Father, but the Son is not less than the Father because He proceeds from the Father, so the Holy Spirit is not less than the Son because He proceeds from the Son. But listen, you who object!

For the Son has one Father as his cause and source, and the Holy Spirit, as you say, has two causes and two sources, that is, the Father and the Son, and from two, as you say, proceed one; but of the Son you do not say that He is born alone, or proceeds from two, but from one Father. And if you were to say that the Son also has two sources and two causes, the Father and the Holy Spirit, and the Holy Spirit also has two sources and two causes, the Father and the Son, then you would say that the Holy Spirit is equal to the Son.

Now you speak of equality in words, but in deed you belittle it, supposing that the Holy Spirit has two sources and two causes, and the Son has one cause and source. Although the Son is equal in all things to the Father, you cannot say that the Son is the cause and source of the Father. But if you say this, know this: you have confused the Divine order, annoyed God, and perverted the Holy Scriptures. In the same way, if you say that the Holy Spirit proceeds from the Son, you have vexed God, you have confused the essence and order of the Divine Trinity, for the holy Church of God teaches that the Father has a Son and has the Holy Spirit, and we do not say that these are three gods, but that all three are one God, and they are equal both in essence and in divinity, and power.

And although They are equal in all things, the Father is the source and cause of the Son and the Holy Spirit, and not the Son of the Father, nor the Spirit of the Holy Son, nor the Son of the Holy Spirit. Just as the Holy Spirit is neither the source nor the cause of the Son, so the Son is neither the source nor the cause of the Holy Spirit. But we say and believe that the Father is the cause of both, ineffable and incomprehensible to angels and to men, as the great Dionysius says: God is essentially incomprehensible, but His creation enables us to know and glorify Him, because through the visible we receive certain testimonies about God.

As the circle of the sun and the ray and the light are inseparable, so are the Father, the Son, and the Holy Spirit: the Father is the cause of the two, but not older, just as the sun is not older than the ray and the light. And if you say that the circle of the sun comes first, and the ray and the light later, you will say it wrong. And if you say that light and ray are before the solar circle, you will also say it wrong. You see that although all are one, the solar circle is the source and cause of both light and rays, just as the Father is the source and cause of the Son and the Holy Spirit.

And if anyone says that the cause of the solar circle is a ray and light, he will say it wrongly, and everyone will answer him: you are possessed, and you do not understand simple things. In the same way, he who says that the cause and source of the Father is the Son and the Holy Spirit will say it wrong, just as he is wrong who says that the cause and source of the Holy Spirit is not only the Father, but also the Son. Although among the Persons of the Holy Trinity there is not One Who was in the beginning and One Who was later, the source and cause of the Son and the Holy Spirit is the Father, and the Son Himself bears witness to Himself, saying: "My Father is greater than I" (John 14:28).

This is said in a human way, but even more so as a judgment about the cause and source: for the Son was born of the Father, and not the Father of the Son. And if anyone says that the Holy Spirit proceeds from the Son, he asserts that just as the Father is the cause and source of the Son and the Holy Spirit, so the Son is the cause and source of the Holy Spirit. But if the Son, like the Father, were the source and cause of the Holy Spirit, then just as the Son said of the Father, "He is greater than I," so the Holy Spirit would say, "The Son is greater than Me, because He is My cause, and I proceed from Him." But this is not said anywhere!

Although in the Holy Trinity there is no One Who was before and One Who was afterwards, and the Father, the Son, and the Holy Spirit are inseparably present, yet the Father is the one cause and source of the Son and the Holy Spirit, and the Son is not the source of the Holy Spirit. But if anyone says that the Son is also the source and cause of the Holy Spirit, for He proceeds also from the Son, he annoys God and produces the most evil confusion, all the more so since, according to Gregory the Theologian, in this case, God is also vexed and confused, and the creation is burdened with the dishonor of God.

And who would dare to speak of the Divine essence with an abominable tongue and filthy flesh, and not to learn from the Holy Scriptures, the writings of the prophets and apostles, from our holy and venerable and God-bearing fathers, thus gathering burning coals on his head? Therefore, we have chosen the testimonies from the holy books, and not our own, and have written them down in order, since they lead us to the right faith and do not allow us to get lost or perish.

For, wearing the Apostolic Orthodoxy, the teachings of the Holy Councils and the teachings of our holy great-eminent fathers, as royal attire, we will become heirs of the Heavenly Kingdom – by the grace of the true, life-giving, omnipotent and omnipotent Holy Spirit, Who proceeds from the Father, and not from the Son, Who is due to worship and glorification together with the Father and the Son, and Who spoke through the prophets.

The believer is "truly an Israelite, in whom there is no guile" (John 1:47), and such a person has truly come to know what God is and how it is proper to reason about God! In addition, one must know how to worship the Lord God now. When you worship the Lord your God in the holy church of God or anywhere else, then with all your heart and mind and thoughts, lift up the sight of your mind to the Holy, One-in-Essence and Life-Giving Trinity — in your thoughts and in your pure heart; and call Him the One God Father, and Son, and Holy Spirit, Creator and Creator of things visible and invisible.

Lift up your sensual eyes to the Divine and all-honorable icon of the Holy and One-in-Essence and Life-Giving Trinity, or to the Divine-human image of our Lord Jesus Christ, or to His Most-Pure Mother, or to any of the saints, or to His Precious and Life-Giving Cross, or to the Holy Gospel, or to the Most Pure Divine Mysteries, or to the Holy Churches, or to the consecrated vessels in which the Divine Mysteries are performed, or to the holy relics, — and worship them with your soul and body with your senses.

As it is proper to worship — with the soul in thought and in the body sensually — listen attentively. When you arise to pray to the Lord Your God, first of all establish a law for yourself — not to stand lazily, paralyzed and careless, but in such a way as not to think about vain and perishable things; besides, let the disorderly voices be silent and the movements and waving of the hands be subdued, let us present them to God as if bound and tightened, and let us set our feet decently, and let us banish all earthly things from our thoughts: rancor and anger, rage and hatred and carnal lusts, and let us force our eyes to tears, and let us direct ourselves entirely to heaven.

And let us stand as the priest says: "Let us become good." And "to stand well" at this time means to stand as it befits God, with fear and trembling, and with a sober and cheerful soul. An archer who wants to shoot arrows successfully first tries to stand up properly, and standing with attention against the banners, he carefully takes up the arrows. In the same way, you, wishing to strike the evil devil at the head, first take care of the decency of the senses, then of the well-being of your inner thoughts, in order to safely shoot arrows at the devil, that is, pure prayer.