All right, this is getting a bit out of hand. First point is that “divine inspiration” pf the Bible, whatever an individual may mean by the term, is only tangentially related to the question of Scriptural evidence of the Trinity. (A good bit of evidence on this point would be the posts of cmkeller and zev_steinhart, devout Orthodox Jews who do believe in the divine inspiration of Scripture but not in the Trinity.) Second, I get the distinct impression that people generally do not understand what is meant by “divine inspiration.” The idea that God propria persona dictated the precise text of the Bible to its human ‘authors’ like a 1940s executive dictating a letter to his secretary, is held only by a minority of the literalist inerrantist fundamentalists, much less the mainstream churches Catholic and Protestant. Rather, it’s something more like “Cecil inspires Dopers to fight ignorance in their posts,” where nobody thinks that implies him calling one of us up to say, “Listen, post this to that IMHO thread…” or perhaps an advocacy group which “inspires” its membership to support its goals by writing in their own words, supplying some helpful evidence they may quote in their letters if they so choose. Having grasped the meaning of a given term, I can then explain it to others.
Further, “the Bible” is a collection of those works, in a variety of genres, that seemed to the early Church to accurately reflect the evolving understanding of the Israelites, Jews, and first Christians about the God in whom they believed. When someone brings to a book compiled more than 1600 years ago the standards of “objective history and biography” which are less than 250 years old, one is sure to go astray. The Jews taught by haggadah: story, fable, parable, and so did Jesus. The style in which the historical books were written is the pre-modern one that sees God influencing and judging the people in His world. The Gospels are Plutarchian biographies, painting Jesus in four different roles I could go on at length on this, but let me leave it with one thought: in a day before Gregg Shorthand and Dictaphones, what was presented as “a teaching by Leader X” was always a reconstruction by the author, ideally true to the speaker’s subject and concepts but no more verbatim than a modern ‘indirect quotation’ (e.g. “Monavis said that the idea of inspiration is unfalsifiable”) where the author (me) is responsible, not for proving the speaker (Monavis) said those exact words, but rather for reporting accurately the meaning of what she said. This becomes important in analyzing the content of various Bible books.
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It’s also important to distinguish between the Triune God and the Doctrine of the Trinity. The first is simply a reporting of the experiences of the first Christians; the second is a human explication, using the terms and categories of Aristotelian logic, to explain the apparent paradox in a way hat made sense to the people of the time.
Further, distinguish between ‘god’, an entity with superhuman powers, and God, an omnipotent, omniscient being. It is trivially simple to show that, while there may be polytheistic pantheons of gods, there can be only one God, as two would interfere with each other’s omnipotence, and plausibly omniscience as well. Hence there is only (at most) one God.
Now, I ask to be granted one presumption: there existed an itinerant rabbi xalled Yeshua bar Mariam. I am explicitly avoiding calling him “Jesus Christ” to avoid the baggage that term carries; we are speaking here and for the moment of a human being, about as well documented as Socrates, Gautama, or Zoroaster. A robust skepticism could call any one of them a human invention, but the majority of people would consider that they did exist, even if some hard-to-believe stories accreted to the historical base.
Now, after what the first Christians believed themselves to have experienced, their attitude was, “When we see Jesus, we see God.” (Note this is an assertion about their perceptions, not one about objective reality.) And further, Jesus had promised, and shortly thereafter the first Christians experienced, the presence of the Holy Spirit as God active in their everyday lives.
Now, the loving Father of whom Jesus had taught, Jesus himself, and the Holy Spirit are three distinct personal entities. But the Israelites and then the Jews had been firm on the idea there is only one God.
Now, the Greek text uses theos (properly declined) to describe the Father, Jesus, and the Holy Spirit, indifferently. They did not sort out the idea this was a paradox; it was a ‘fact’ of their existence, something they had experierienced in their own lives. They did not sort out the paradox for much the same reason as they did not define the morality of heart transplants – it would be the answer to a question no one had yet asked.
As time went by and experience gave way to expression of faith, the question did come up. And the Council of Nicaea roughed out an answer, refined 50 years later by one of the Councils of Constantinople.
But the key point to me is that the Doctrine of the Trinity is a human construct intended to explicate how one God can be three distinct Persons. Its value is simply in giving a philosophical ‘handle’ on an apparent paradox.
Beliief in Father, Son, and Holy Spirit, one God, is an essential of Christianity. (With apologies to Mormons, JWs, Oneness Pentecostals, UUists, etc.: you’re privileged to believe what you wish, but I’m speaking of traditional Christianity here.) That is to be read as “belief in persons”, much as one might say he or she believes in his/her fiance/e/spouse, i.e., puts his/her trust in that other person. Adherence to a theological definition is quite a different thing – if it ‘works’ for you, helps clarify the apparent paradox, fine, adhere to it; if not, believe in a Triune God and resolve the question, if you need to, by a means more amenable to your needs. (I like the idea of setting up a Modalist individual-in-three-roles and a Tritheist three-people-in-one-corporation, then noting the problems witje each and suggesting the truth about the Trinity lies in the area between them.