Why was there no Trinity controversy at the time of Acts?
In the New Testament, a number of historical controversies are described, from overzealous speaking in tongues in Corinth to the Jerusalem council which decided whether or not new Gentile converts needed to keep the Law of Moses. However, what is strikingly absent from the first century is a controversy over a new definition of God.
Imagine that a unitarian missionary came to your church and started preaching that God is only the Father (not the Father, Son, and Holy Spirit). Wouldn’t that cause controversy? Of course it would. People who believe one thing about God don’t just change the moment they hear a new idea. So, what about in the first century? You’ve got all of these Jewish communities throughout the Mediterranean world who are strictly monotheistic, and these Christians come to town preaching a message about the Trinity. Wouldn’t that cause problems? Of course it would. But, where is the evidence of this?
In the entire New Testament we find no controversy over the Trinity, to such a degree that it is never even spelled out clearly. Isn’t the simplest explanation that this doctrine just wasn’t around yet?