Ah, good point. I can rationally, i.e. using the rules of logic, argue about the properties of Russell's teapot, the Invisible Pink Unicorn or Mr Spock's thoughts on time travel, all the time mindful of the fact that none of them are factually real.
Rationally chasing one's tail?
It is my understanding that hard-core monotheism implies that God is not one of many parties, there is only God and his creation, so just as he separated the land from the waters of his creation, he separated truth from lies, justice from injustice no? Genesis reports that he is not foreign to untruth, e.g. what he told the woman about the fruit of knowledge of good and evil. And yes, there are valid rational explanations of this behavior that rationalize why he behaved in this way without straying into the realm of lies.
I'm going to tread in where I shouldn't be, my understanding is limited. As I understand (and if someone has better understanding from the Jewish POV, please correct me), words have power. Specifically, G-d's words have creative power. G-d spoke, and it came to be. (And why I find it irrational that G-d could be a liar) G-d created all that we can understand by the power of His spoken word, the word was the tool or manner in which G-d created all there is.
With that in mind, the opening of the Gospel of John takes on a bit different meaning, "In the beginning was the Word (logos), and the Word was with G-d, and the Word was G-d, the same was in the beginning with G-d."
Whether one believes Christ is a manifestation of G-d or not is irrelevant to this point just now, insomuch as words have creative power. Surely even esoteric practices teach as much? I've read that Tibetan Buddhists credit the AUM as the sound of the Earth, its creation and continuation, its rhythm, its pulse.
It becomes an in-depth study that I haven't pursued, but I intuit.
And then we have the enigmatic character of Melchizedek, who "was not born and did not die." This is the Priest-King of Salem that blessed Abraham. Little is said of him in the Bible apart from what I just wrote, yet Christ is said in the books of Paul to be "a Priest after the Order of Melchizedek." I am certain the teachings of Judaism would have something to say about Melchizedek, I've not heard or read. Nothing in the archeological record to indicate Melchizedek existed - so do I presume he is fictional? He seems to play an important role in the life of Abraham, and so the foundation of the monotheistic faith that would become Judaism, and by a circuitous route Islam. He is a seminal character in the mythos.
I have one more limb to go out on... My understanding of the Hindu (forgive me if I have the name wrong) pantheon is not a host of different gods, but different aspects of one G-d. Since the Vedas are widely acknowledged to be the oldest religious texts (still in use), a reasonable speculation might be the Egypto-Greco-Roman pantheon was a misinterpretation or misapplication of this concept. This thought is two edged; either it explains a Christian possibility, or it explains a Pagan possibility that was merged into Christianity - "baptized" as it were, as I've read before in similar context. The idea of one G-d having multiple aspects is an ancient belief.
So when the Gospel of John picks up a bit further on and says, "And the Word was made flesh, and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father,) full of grace and truth," it is natural to a Christian to make the association between the Christ and G-d the Father. Particularly so when layered upon the passage from Isaiah: "The LORD hath made bare his holy arm in the eyes of all the nations; and all the ends of the earth shall see the salvation of our God."
