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What the Early Church Believed: One True God

The first Christians, like the Jews before them, were fiercely monotheistic, willing to die horrible martyrs’ deaths in the Coliseum—being slain by gladiators, devoured by wild animals, crucified, or tied to a stake and turned into human torches—rather than concede the existence of any other gods.

This adamant insistence on monotheism is taken directly from the teaching of the Bible. Thus, in John 17:3 Jesus addresses his Father, saying, “And this is eternal life, that they know you—the only true God.”

Despite the clarity of this statement and numerous others concerning the existence of one—and only one—God, some modern groups reject Jesus’ teaching. Mormons, for example, claim that there is an innumerable multitude of gods and that new gods are being formed all the time. Some gods are supposed to be older than the Father, and it is taught that human beings can eventually become gods through practicing Mormonism.

This is in direct contradiction to the declaration of God himself in the book of Isaiah: “‘You are my witnesses,’ says the Lord, ‘and my servant whom I have chosen, that you may know and believe me and understand that I am he. Before me no god was formed, nor shall there be any after me’” (Isa. 43:10).

The first Christians took God at his word and were willing to stake even their lives on the certainty that there is only one God.

The proposition that God is one constitutes one of the central tenets in the dogma of the Trinity. In other tracts, (e.g., The Divinity of Christ, The Eternal Sonship of Christ, Filioque, God in Three Persons, The Trinity) we show that the Fathers also taught the other aspects of the Trinity.

Pope Clement I

“What think you, beloved? Did not Moses know beforehand that this would happen? Undoubtedly he knew; but he acted thus, that there might be no sedition in Israel, and that the name of the true and only God might be glorified; to whom be glory for ever and ever. Amen” (Letter to the Corinthians 43 [A.D. 80]).

Ignatius of Antioch

“The prophets, who were men of God, lived according to Jesus Christ. For that reason they were persecuted, inspired as they were by his grace to convince the disobedient that there is one God, who manifested himself through his Son, Jesus Christ, who is his Word proceeding from silence, and who was in all respects pleasing to him that sent him” (Letter to the Magnesians 8:1 [A.D. 110]).

Justin Martyr

“There will be no other God, O Trypho, nor was there from eternity any other existing . . . but he who made and disposed all this universe. Nor do we think that there is one God for us, another for you, but that he alone is God who led your fathers out from Egypt with a strong hand and a high arm. Nor have we trusted in any other, for there is no other, but in him in whom you also have trusted, the God of Abraham, and of Isaac, and of Jacob” (Dialogue with Trypho the Jew 11 [A.D. 155]).


“[God] himself also by his own prophets testifies, when he says, ‘I, God, am the first,’ and after this, ‘And beside me there is no other God’ [Isa. 44:6]. On this account, then, as I before said, God did not, when he sent Moses to the Hebrews, mention any name, but by a participle he mystically teaches them that he is the one and only God” (Address to the Greeks 21 [A.D. 170]).


“Of his own accord and by his own power he made all things and arranged and perfected them; and his will is the substance of all things. He alone, then, is found to be God; he alone is omnipotent, who made all things; he alone is Father, who founded and formed all things, visible and invisible, sensible and insensate, heavenly and earthly, by the Word of his power. And he has fitted and arranged all things by his wisdom; and while he comprehends all, he can be comprehended by none. He is himself the designer, himself the builder, himself the inventor, himself the maker, himself the Lord of all” (Against Heresies 2:30:9 [A.D. 189]).


“The object of our worship is the one God, who, by the word of his command, by the reason of his plan, and by the strength of his power, has brought forth from nothing for the glory of his majesty this whole construction of elements, bodies, and spirits; whence also the Greeks have bestowed upon the world the name ‘cosmos’” (Apology 17:1 [A.D. 197]).

“There is only one God, and none other besides him, the Creator of the world who brought forth all things out of nothing through his Word, first of all sent forth” (Demurrer Against the Heretics 13:1 [A.D. 200]).

“We do indeed believe that there is only one God, but we believe that under this dispensation, or, as we say, oikonomia, there is also a Son of this one only God, his Word, who proceeded from him and through whom all things were made and without whom nothing was made” (Against Praxeas 2 [A.D. 216]).

The Recognitions of Clement

“[T]hough there are many that are called gods, there is but one true God, according to the testimonies of the scriptures” (Recognitions of Clement 3:75 [A.D. 221]).

The Clementine Homilies

“[T]he Scripture says, ‘As I live, says the Lord, there is no other God but me. I am the first, I am after this; except me there is no god’ [Is. 44:6]. And again: ‘You shall fear the Lord your God, and him only shall you serve’ [Deut. 6:13, Matt. 4:10]. And again: ‘Hear, O Israel, the Lord your God is one Lord’ [Deut. 6:4]. And many passages besides seal with an oath that god is one, and except him there is no god” (Clementine Homilies 16:7 [A.D. 221]).


“The specific points which are clearly handed down through the apostolic preaching are these: First, that there is one God who created and arranged all things, and who, when nothing existed, called all things into existence, and that in the final period this God, just as he had promised beforehand through the prophets, sent the Lord Jesus Christ. Secondly, that Jesus Christ himself, who came, was born of the Father before all creatures; and after he had ministered to the Father in the creation of all things, for through him all things were made” (The Fundamental Doctrines 1:0:4 [A.D. 225]).


“The one God, the first and only, both Creator and Lord of all things, had nothing co-eternal. . . . No, he was one, to himself alone. And when he so willed, he created those things which before had no existence other than in his willing to make them and inasmuch as he had knowledge of what would be, for he also has foreknowledge” (Refutation of All Heresies [A.D. 228]).


“We must therefore believe, according to the rule prescribed, on the Lord, the one true God, and consequently on him whom he has sent, Jesus Christ, who by no means, as we have said, would have linked himself to the Father had he not wished to be understood to be God also, for he would have separated himself from him had he not wished to be understood to be God” (Treatise on the Trinity 16 [A.D. 235]).

“God the Father, founder and Creator of all things, who alone knows no beginning, who is invisible, immeasurable, immortal, and eternal, is one God. Neither his greatness nor his majesty nor his power can possibly be—I should not say exceeded, for they cannot even be equaled. From him . . . the Word was born, his Son. . . . And the latter, since he was born of the Father, is always in the Father. And I indeed say always . . . he that exists before all time must be said to have been in the Father always, for he that exists before all time cannot be spoken of in relation to time. . . . [A]ssuredly, he [the Son] is God, proceeding from God, causing, as Son, a second person after the Father, but not taking away from the Father the fact that God is one” (ibid., 31).

Gregory the Wonderworker

“We therefore acknowledge one true God, the one first cause, and one Son, very God of very God, possessing of nature the Father’s divinity—that is to say, being the same in substance with the Father; and one Holy Spirit, who by nature and in truth sanctifies all, and makes divine, as being of the substance of God. Those who speak either of the Son or of the Holy Spirit as a creature we anathematize” (A Sectional Confession of Faith 15 [A.D. 262]).

“There is one God. . . . There is a perfect Trinity, in glory and eternity and sovereignty, neither divided nor estranged. Wherefore there is nothing either created or in servitude in the Trinity; nor anything superinduced, as if at some former period it was nonexistent, and at some later period it was introduced. And thus neither was the Son ever wanting to the Father, nor the Spirit to the Son; but without variation and without change, the same Trinity abides ever” (Declaration of Faith [A.D. 265]).

Council of Nicaea I

“We believe in one God, the Father Almighty, maker of heaven and earth, of all things, visible and invisible” (Creed of Nicaea [A.D. 325]).

Epiphanius of Salamis

“We believe in one God, the Father Almighty, maker of all things, both visible and invisible; and in one Lord Jesus Christ, the Son of God, begotten of God the Father, only-begotten, that is, of the substance of the Father; God of God, light of light, true God of true God; begotten, not made; consubstantial with the Father; through whom all things were made, both those in heaven and those on earth, both visible and invisible; who for us men and for our salvation came down and took flesh, that is, was born perfectly of the holy ever-virgin Mary by the Holy Spirit, was made man, that is, he received perfect man, soul and body and mind and all that man is, except sin” (The Man Well-Anchored 120 [A.D. 374]).

Patrick of Ireland

“[T]here is no other God, nor has there been heretofore, nor will there be hereafter, except God the Father unbegotten, without beginning, from whom is all beginning, upholding all things, as we say, and his Son Jesus Christ, whom we likewise to confess to have always been with the Father—before the world’s beginning. . . . Jesus Christ is the Lord and God in whom we believe . . . and who has poured out on us abundantly the Holy Spirit . . . whom we confess and adore as one God in the Trinity of the sacred Name” (Confession of St. Patrick 4 [A.D. 452]).

Fulgentius of Ruspe

“True religion consists in the service of the one true God. For it is truth itself that there is one God; and just as, besides the one truth, there is no other truth, so too, besides the one true God there is no other true God. For the one truth itself is naturally one true divinity. And thus one cannot speak truthfully of two true gods, because it is not possible for the truth itself, naturally one, to be divided” (Letters 8:10 [A.D. 519]).

NIHIL OBSTAT: I have concluded that the materials
presented in this work are free of doctrinal or moral errors.
Bernadeane Carr, STL, Censor Librorum, August 10, 2004

IMPRIMATUR: In accord with 1983 CIC 827
permission to publish this work is hereby granted.
+Robert H. Brom, Bishop of San Diego, August 10, 2004

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