If we modify the post putting the word (some),I would say, its true, too....
I can accept that amendment, the insertion of the term "some", to my previous post.
As I wrote it, I was thinking about more than just the issue of the development of trinitarian thought. And when one considers the total corpus of Jewish writing at the time, I think that one can show that on the whole Jewish thought of that day and today are vastly different from a number of reasons, only one of which would be that some Jews of that day believed in a more relaxed form of monotheism in attributing personality to things such as God's wisdom, God's spirit, God's word that a Muslim reading those ancient texts today would consider those views shirk, though Jews of that day would have still considered themselves to be monotheists. It was from those personifications of aspects of the divine being that Christians then proceeded to find ground on which the concepts that became eventually known as the doctrine of the Trinity developed.
I don't think that those first century Jews/Christians (including, maybe especially, Paul) ever once thought of themselves as anything other than monotheists just like Jewish brothers who were not Christians. But, unlike their non-Christian Jewish brothers they found in this particular strain of Jewish thought that was dominant in their time, reason to accept the idea that Jesus might indeed be the very presence of this one God now making himself known in the flesh even as he still reigned in heaven and also simultaneously became a living presence in their lives via his Spirit.
I wouldn't say those SOME second temple Jews accepted the christian exegesis of Jewish scriptures....
as the fact, it was them who invented such exegesis (details later)....
Again, agreed. As I alluded to above, it was the presence of that sort of exegesis that those who followed Christ relied upon as they looked back upon their time with him and came to the conclusion that he was indeed God come among them. The question I would have of them, that I don't think we can clearly answer from the Christian scriptures, is when, in their mind did Jesus become divine? Had Jesus always been God? Certainly the birth narratives were written to make that point. Or was it only because of his complete and lifelong submission to the Father that he was elevated by the Father to that status? That position being more reflected in Paul's writings, which makes it all the more ironic how Muslims attack Paul.
One mistake that I think far too many people make, both those who try to defend and those who try to refute Christian doctrine today, is to think that Christian theology was fully formed from the beginning. The truth is that the disciples (and there were many more than 12) who had followed Jesus were lost and did not know what to think at first. That is one of the reasons they are reported as hiding in the Upper Room. And even when they emerged from their to proclaim Jesus' message, while I do think that we see in Peter's initial sermon recognition of the Lordship (and therefore divinity) of Christ, that message was initially a call simply an eschatological kerygma. By that I mean, they taught that Jesus was God's instrument for bringing to fulfillment the promise of the end times and the setting of everything right in the world. This primitive kerygma has as its focus the death and exaltation of Jesus and the proclamation of his Lordship. And by Lordship they meant so much more than a mere honorific title. It was indeed a challenge to the emperor who had given himself the title "Lord of the Universe," rejected by all Jews because such a claim was to usurp God's status. So, when Peter made such a claim with regard to Jesus he was very knowingly either claiming that Jesus was God come to make himself known and complete what God had promised he would do, or that Jesus was a usurper of God's throne. As the latter does not fit the rest of what Peter had to say about Jesus, it seems that Peter was making claims for Jesus divine nature from the very beginning. But much of what that meant and other ideas had not been thought through. I believe we see these develop in the scriptures not instantaneously, but over time. An example would be the use of the term "Christ". At first it was simply the Greek translation of Jesus' role as the Messiah, but in time it became to be used first as a title and then almost as a proper name. Even Jesus' own message of the kingdom of God would be fleshed out more over time.
Yet while, in a sense, all theology will continue to develop as people continue to reflect on it, it also seems to me that the essential substance of this new and specifically Christian (vis-a-vis Jewish) theology would reach completion before the passing of the first generation of the church. The books that were to become the corpus of the New Testament were all completed and in widespread distribution. The rituals for baptism, celebration of the eucharist, and other rituals connected with worship in the emergent church had been developed and disseminated through a manual such as the Didache. And the process of the transmission of authority from the apostles to the next generation of leaders had been established. But those future generations would continue the process of reflection on what had been established by Christ and asserted by the apostles and it would be those reflections that would provide the manner in which doctrines such as the Trinity would be articulated -- based on their understandings of what had been proclaimed by the first generation, which you and I (even if no one else does) seem to agree found fertile soil for germination in the way turn of the millenium Judiasm conceived of God.