But what do we see in the Early Church Fathers—those teachers of the church who existed contemporaneously with the Apostles or shortly after them? What do these men who were taught by the Apostles or one of their disciples have to say about the Trinity?
Clement of Rome (around the end of the first century) wrote as follows:
Have we not [all] one God and one Christ? Is there not one Spirit of grace poured out upon us? [ANF 1: 17; First Epistle of Clement; ch. XLVI]
St. Justin Martyr in his First Apology, written during the first half of the Second Century, elegantly defends the Christians against the charge of atheism hurled at them by the pagans.
And we confess that we are atheists, so far as gods of this sort are concerned, but not with respect to the most true God, the Father of righteousness and temperance and the other virtues, who is free from all impurity. But both Him, and the Son (who came forth from Him and taught us these things, and the host of the other good angels who follow and are made like to Him), and the prophetic Spirit, we worship and adore, knowing them in reason and truth, and declaring without grudging to every one who wishes to learn, as we have been taught. [ANF 1: 164; ch. VI]
Several things should be noted in this passage. First, the mention of all three persons of the Blessed Trinity is made in an almost matter-of-fact manner. Secondly, notice that he says that this is “as we have been taught.” He is not declaring some new doctrine or fresh revelation but is simply stating the faith as he has been taught it.
In A Plea for the Christians, Athenagoras (c. 176 A.D.) addressed the same charge that Justin Martyr had earlier.
Who, then, would not be astonished to hear men who speak of God the Father, and of God the Son, and of the Holy Spirit, and who declare both their power in union and their distinction in order, called atheists? [ANF 2: 133; ch. X]
Irenaeus who battled valiantly against the Gnostics would no doubt be surprised to hear that the doctrine of the Trinity (which he believed and taught) was an invention of the Gnostics. A good example of his belief is found in Against Heresies written near the end of the Second Century.
Therefore have the Jews departed from God, in not receiving His Word, but imagining that they could know the Father [apart] by Himself, without the Word, that is, without the Son; they being ignorant of that God who spake in human shape to Abraham, and again to Moses, saying, “I have surely seen the affliction of My people in Egypt, and I have come down to deliver them.” For the Son, who is the Word of God, arranged these things beforehand from the beginning, the Father being in no want of angels, in order that He might call the creation into being, and form man, for whom also the creation was made; nor, again, standing in need of any instrumentality for the framing of created things, or for the ordering of those things which had reference to man; while, [at the same time,] He has a vast and unspeakable number of servants. For His offspring and His similitude do minister to Him in every respect; that is, the Son and the Holy Spirit, the Word and Wisdom; whom all the angels serve, and to whom they are subject. [ANF 1: 470; ch. VII, par. 4]
In Theophilus to Autolycus , Theophilus is credited with the first use of the word “Trinity” around the year 181 A.D.
In like manner also the three days which were before the luminaries, are types of the Trinity, of God, and His Word, and His wisdom. [ANF 2:100-1; book II, ch. XV]
While we may not agree with his typological interpretation, there is no doubt that he does believe in the Trinity. The note given in ANF is instructive:
“the use he makes of it [the word Trinity] is familiar. He does not lug it in as something novel: “types of the Trinity,” he says, illustrating an accepted word, not introducing a new one.”
Hipplytus of Rome writing in the early Third Century writes the following in his Against the Heresy of One Noetus :
A man, therefore, even though he will it not, is compelled to acknowledge God the Father Almighty, and Christ Jesus the Son of God, who, being God, became man, to whom also the Father made all things subject, Himself excepted, and the Holy Spirit; and that these, therefore, are three. But if he desires to learn how it is shown still that there is one God, let him know that His poweris one. As far as regards the power, therefore, God is one. But as far as regards the economy there is a threefold manifestation, as shall be proved afterwards when we give account of the true doctrine. [ANF 5:226, ch. 8]
We accordingly see the Word incarnate, and we know the Father by Him, and we believe in the Son, (and) we worship the Holy Spirit. [ANF 5:228, ch. 12]
For the Father indeed is One, but there are two Persons, because there is also the Son; and then there is the third, the Holy Spirit. [ANF 5:228; ch. 14]
As a matter of fact, the whole of this work refuting Noetus is a powerful tool in combating his heresy which was modalistic monarchianism, aka, Oneness.
From this brief overview, it should be quite clear that though the full explication of the Trinity may have come later, the Fathers of the Early Church were definitely Trinitarian in their beliefs. They did not add a new doctrine but explained one that had been handed down fro
