The way, the truth, and the life – Jesus Christ, page-37

I think that possibly some points were missed in the Standford article,
Scripture was thought to be written after much of doctrine was already established so much of it really reflects already established beliefs.
Just because they hadn't assigned a word for the Trinity doesn't mean it wasn't an established belief.
The fact that far-flung churches appear to have embraced a Trinity belief in the first century indicates that the belief was formed early on.
The Trinity belief was probably taken for granted and a challenge in the 3rd century forced the church to formulise the belief.
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Just a few thoughts in response to the interesting article.