from wikipedia:
“In 325, the Council of Nicaea adopted a term for the relationship between the Son and the Father that from then on was seen as the hallmark of orthodoxy; it declared that the Son is “of the same substance” (ὁμοούσιος) as the Father.”
“Saint Athanasius, who was a participant in the Council, stated that the bishops were forced to use this terminology, which is not found in Scripture, because the Biblical phrases that they would have preferred to use were claimed by the Arians to be capable of being interpreted in what the bishops considered to be a heretical sense…”
“the Trinity took place in the 4th century, with a group of men known as the Church Fathers.”
“The Nicene Creed, which is a classic formulation of the doctrine of the Trinity, uses “homoousios” (Greek for “of the same essence”) of the relation of the Son’s relationship with the Father…”
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In 325, the Council of Nicaea…
In 382 AD the Council of Rome came up with the canon of books for the Bible decreed by Pope Damascus.
the canon of the Bible took place in the 4th century, with a group of men known as the Church Fathers
So…
Our teacher of these things is Jesus Christ, who also was born for this purpose, and was crucified under Pontius Pilate, procurator of Judea, in the times of Tiberius Caesar; and that we reasonably worship Him, having learned that He is the Son of the true God Himself, and holding Him in the second place, and the prophetic Spirit in the third, we will prove." Justin Martyr, First Apology, 13 (A.D. 155).
“For God did not stand in need of these [beings], in order to the accomplishing of what He had Himself determined with Himself beforehand should be done, as if He did not possess His own hands. For with Him were always present the Word and Wisdom, the Son and the Spirit, by whom and in whom, freely and spontaneously, He made all things, to whom also He speaks, saying, ‘Let Us make man after Our image and likeness;’ He taking from Himself the substance of the creatures [formed], and the pattern of things made, and the type of all the adornments in the world.” Irenaeus, Against Heresies, 4,20:1 (A.D. 180).
“In the course of time, then, the Father forsooth was born, and the Father suffered, God Himself, the Lord Almighty, whom in their preaching they declare to be Jesus Christ. We, however, as we indeed always have done and more especially since we have been better instructed by the Paraclete, who leads men indeed into all truth), believe that there is one only God, but under the following dispensation, or oikonomia, as it is called, that this one only God has also a Son, His Word, who proceeded from Himself, by whom all things were made, and without whom nothing was made. Him we believe to have been sent by the Father into the Virgin, and to have been born of her–being both Man and God, the Son of Man and the Son of God, and to have been called by the name of Jesus Christ; we believe Him to have suffered, died, and been buried, according to the Scriptures, and, after He had been raised again by the Father and taken back to heaven, to be sitting at the right hand of the Father, and that He will come to judge the quick and the dead; who sent also from heaven from the Father, according to His own promise, the Holy Ghost, the Paraclete, the sanctifier of the faith of those who believe in the Father, and in the Son, and in the Holy Ghost. That this rule of faith has come down to us from the beginning of the gospel, even before any of the older heretics, much more before Praxeas, a pretender of yesterday, will be apparent both from the lateness of date which marks all heresies, and also from the absolutely novel character of our new-fangled Praxeas.” Tertullian, Against Praxeas, 2 (post A.D. 213).
"Bear always in mind that this is the rule of faith which I profess; by it I testify that the Father, and the Son, and the Spirit are inseparable from each other, and so will you know in what sense this is said. Now, observe, my assertion is that the Father is one, and the Son one, and the Spirit one, and that They are distinct from Each Other. This statement is taken in a wrong sense by every uneducated as well as every perversely disposed person, as if it predicated a diversity, in such a sense as to imply a separation among the Father, and the Son, and the Spirit. I am, moreover, obliged to say this, when (extolling the Monarchy at the expense of the Economy) they contend for the identity of the Father and Son and Spirit, that it is not by way of diversity that the Son differs from the Father, but by distribution: it is not by division that He is different, but by distinction; because the Father is not the same as the Son, since they differ one from the other in the mode of their being. For the Father is the entire substance, but the Son is a derivation and portion of the whole, as He Himself acknowledges: My Father is greater than I.’ In the Psalm His inferiority is described as being a little lower than the angels.’ Thus the Father is distinct from the Son, being greater than the Son, inasmuch as He who begets is one, and He who is begotten is another; He, too, who sends is one, and He who is sent is another; and He, again, who makes is one, and He through whom the thing is made is another.” Tertullian, Against Praxeas, 9 (post A.D. 213).