The disciples of the Apostles wrote to each other a lot because of heretical ideas creeping into the congregation. So, the main beliefs of the first Christians are well established and easily cross checked. The reason Christians called Jesus God is because that was one of the MAIN teachings of the apostles. Unitarians are aligned with skeptic scholars to try and cast doubt on scripture. Not much has changed in 2000 years.
Here is a list of nine early church leaders, some taught directly by the apostles who call Jesus God in dozens of instances. This of course supports the traditional reading being discussed in this post.
Polycarp (AD 69-155) was the bishop (city overseer) at the church in Smyrna. Irenaeus tells us Polycarp was a disciple of John the Apostle. In his Letter to the Philippians he says:
Now may the God and Father of our Lord Jesus Christ, and the eternal high priest himself, the Son of God Jesus Christ, build you up in faith and truth...and to us with you, and to all those under heaven who will yet believe in our Lord and God Jesus Christ and in his Father who raised him from the dead.1
Ignatius (AD 50-117) was the bishop (city overseer) at the church in Antioch and also a disciple of John the Apostle. He wrote a series of letters to various churches on his way to Rome, where he was to be martyred. He writes,
Ignatius, who is also Theophorus, unto her which hath been blessed in greatness through the plentitude of God the Father; which hath been foreordained before the ages to be for ever unto abiding and unchangeable glory, united and elect in a true passion, by the will of the Father and of Jesus Christ our God; even unto the church which is in Ephesus [of Asia], worthy of all felicitation: abundant greeting in Christ Jesus and in blameless joy.2
Being as you are imitators of God, once you took on new life through the blood of God you completed perfectly the task so natural to you.3
There is only one physician, who is both flesh and spirit, born and unborn, God in man, true life in death, both from Mary and from God, first subject to suffering and then beyond it, Jesus Christ our Lord.4
For our God, Jesus the Christ, was conceived by Mary according to God’s plan, both from the seed of David and of the Holy Spirit.5
Consequently all magic and every kind of spell were dissolved, the ignorance so characteristic of wickedness vanished, and the ancient kingdom was abolished when God appeared in human form to bring the newness of eternal life.6
For our God Jesus Christ is more visible now that he is in the Father.7
I glorify Jesus Christ, the God who made you so wise, for I observed that you are established in an unshakable faith, having been nailed, as it were, to the cross of the Lord Jesus Christ.8
Wait expectantly for the one who is above time: the Eternal, the Invisible, who for our sake became visible; the Intangible, the Unsuffering, who for our sake suffered, who for our sake endured in every way.9
Justin Martyr (AD 100-165) was an Christian apologist of the second century.
And that Christ being Lord, and God the Son of God, and appearing formerly in power as Man, and Angel, and in the glory of fire as at the bush, so also was manifested at the judgment executed on Sodom, has been demonstrated fully by what has been said.10
Permit me first to recount the prophecies, which I wish to do in order to prove that Christ is called both God and Lord of hosts.11
Therefore these words testify explicitly that He [Jesus] is witnessed to by Him [the Father] who established these things, as deserving to be worshipped, as God and as Christ.12
The Father of the universe has a Son; who also, being the first-begotten Word of God, is even God. And of old He appeared in the shape of fire and in the likeness of an angel to Moses and to the other prophets; but now in the times of your reign, having, as we before said, become Man by a virgin....13
For if you had understood what has been written by the prophets, you would not have denied that He was God, Son of the only, unbegotten, unutterable God.14
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