St. Gregory the Theologian ca. 329-389
But, he says, who in ancient or modern times ever worshipped the Spirit? Who ever prayed to Him? Where is it written that we ought to worship Him, or to pray to Him, and whence have you derived this tenet of yours? We will give the more perfect reason hereafter, when we discuss the question of the unwritten; for the present it will suffice to say that it is the Spirit in Whom we worship, and in Whom we pray. For Scripture says, God is a Spirit, and they that worship Him must worship Him in Spirit and in truth. And again,—We know not what we should pray for as we ought; but the Spirit Itself makes intercession for us with groanings which cannot be uttered; and I will pray with the Spirit and I will pray with the understanding also; —that is, in the mind and in the Spirit. Therefore to adore or to pray to the Spirit seems to me to be simply Himself offering prayer or adoration to Himself…
Over and over again you turn upon us the silence of Scripture. But that it is not a strange doctrine, nor an afterthought, but acknowledged and plainly set forth both by the ancients and many of our own day, is already demonstrated by many persons who have treated of this subject, and who have handled the Holy Scriptures, not with indifference or as a mere pastime, but have gone beneath the letter and looked into the inner meaning, and have been deemed worthy to see the hidden beauty, and have been irradiated by the light of knowledge…Since, then, there is so much difference in terms and things, why are you such a slave to the letter, and a partisan of the Jewish wisdom, and a follower of syllables at the expense of facts?
The New manifested the Son, and suggested the Deity of the Spirit. Now the Spirit Himself dwells among us, and supplies us with a clearer demonstration of Himself. For it was not safe, when the Godhead of the Father was not yet acknowledged, plainly to proclaim the Son; nor when that of the Son was not yet received to burden us further (if I may use so bold an expression) with the Holy Ghost; lest perhaps people might, like men loaded with food beyond their strength, and presenting eyes as yet too weak to bear it to the sun’s light, risk the loss even of that which was within the reach of their powers; but that by gradual additions, and, as David says, Goings up, and advances and progress from glory to glory, the Light of the Trinity might shine upon the more illuminated. For this reason it was, I think, that He gradually came to dwell in the Disciples, measuring Himself out to them according to their capacity to receive Him, at the beginning of the Gospel, after the Passion, after the Ascension, making perfect their powers, being breathed upon them, and appearing in fiery tongues. And indeed it is little by little that He is declared by Jesus, as you will learn for yourself if you will read more carefully. I will ask the Father, He says, and He will send you another Comforter, even the spirit of Truth. This He said that He might not seem to be a rival God, or to make His discourses to them by another authority. Again, He shall send Him, but it is in My Name. He leaves out the I will ask, but He keeps the Shall send, then again, I will send,—His own dignity. Then shall come, the authority of the Spirit.
You see lights breaking upon us, gradually; and the order of Theology, which it is better for us to keep, neither proclaiming things too suddenly, nor yet keeping them hidden to the end. For the former course would be unscientific, the latter atheistical; and the former would be calculated to startle outsiders, the latter to alienate our own people…
This, then, is my position with regard to these things, and I hope it may be always my position, and that of whosoever is dear to me; to worship God the Father, God the Son, and God the Holy Ghost, Three Persons, One Godhead, undivided in honour and glory and substance and kingdom, as one of our own inspired philosophers not long departed showed. Let him not see the rising of the Morning Star, as Scripture says, nor the glory of its brightness, who is otherwise minded, or who follows the temper of the times, at one time being of one mind and of another at another time, and thinking unsoundly in the highest matters. For if He is not to be worshipped, how can He deify me by Baptism? But if He is to be worshipped, surely He is an Object of adoration, and if an Object of adoration He must be God; the one is linked to the other, a truly golden and saving chain. And indeed from the Spirit comes our New Birth, and from the New Birth our new creation, and from the new creation our deeper knowledge of the dignity of Him from Whom it is derived.
This, then, is what may be said by one who admits the silence of Scripture. But now the swarm of testimonies shall burst upon you from which the Deity of the Holy Ghost shall be shown to all who are not excessively stupid, or else altogether enemies to the Spirit, to be most clearly recognized in Scripture. Look at these facts:—Christ is born; the Spirit is His Forerunner. He is baptized; the Spirit bears witness. He is tempted; the Spirit leads Him up. He works miracles; the Spirit accompanies them. He ascends; the Spirit takes His place. What great things are there in the idea of God which are not in His power? What titles which belong to God are not applied to Him, except only Unbegotten and Begotten? For it was needful that the distinctive properties of the Father and the Son should remain peculiar to Them, lest there should be confusion in the Godhead Which brings all things, even disorder itself, into due arrangement and good order. Indeed I tremble when I think of the abundance of the titles, and how many Names they outrage who fall foul of the Spirit. He is called the Spirit of God, the Spirit of Christ, the Mind of Christ, the Spirit of The Lord, and Himself The Lord, the Spirit of Adoption, of Truth, of Liberty; the Spirit of Wisdom, of Understanding, of Counsel, of Might, of Knowledge, of Godliness, of the Fear of God. For He is the Maker of all these, filling all with His Essence, containing all things, filling the world in His Essence, yet incapable of being comprehended in His power by the world; good, upright, princely, by nature not by adoption; sanctifying, not sanctified; measuring, not measured; shared, not sharing; filling, not filled; containing, not contained; inherited, glorified, reckoned with the Father and the Son; held out as a threat; the Finger of God; fire like God; to manifest, as I take it, His consubstantiality); the Creator-Spirit, Who by Baptism and by Resurrection creates anew; the Spirit That knows all things, That teaches, That blows where and to what extent He lists; That guides, talks, sends forth, separates, is angry or tempted; That reveals, illumines, quickens, or rather is the very Light and Life; That makes Temples; That deifies; That perfects so as even to anticipate Baptism, yet after Baptism to be sought as a separate gift; That does all things that God does; divided into fiery tongues; dividing gifts; making Apostles, Prophets, Evangelists, Pastors, and Teachers; understanding manifold, clear, piercing, undefiled, unhindered, which is the same thing as Most wise and varied in His actions; and making all things clear and plain; and of independent power, unchangeable, Almighty, all-seeing, penetrating all spirits that are intelligent, pure, most subtle (the Angel Hosts I think); and also all prophetic spirits and apostolic in the same manner and not in the same places; for they lived in different places; thus showing that He is uncircumscript.
They who say and teach these things, and moreover call Him another Paraclete in the sense of another God, who know that blasphemy against Him alone cannot be forgiven, and who branded with such fearful infamy Ananias and Sapphira for having lied to the Holy Ghost, what do you think of these men? Do they proclaim the Spirit God, or something else? Now really, you must be extraordinarily dull and far from the Spirit if you have any doubt about this and need some one to teach you. So important then, and so vivid are His Names. Why is it necessary to lay before you the testimony contained in the very words? And whatever in this case also is said in more lowly fashion, as that He is Given, Sent, Divided; that He is the Gift, the Bounty, the Inspiration, the Promise, the Intercession for us, and, not to go into any further detail, any other expressions of the sort, is to be referred to the First Cause, that it may be shown from Whom He is, and that men may not in heathen fashion admit Three Principles. For it is equally impious to confuse the Persons with the Sabellians, or to divide the Natures with the Arians. (Oration 31.12, 21, 26-30)