Why call this character "My God"? And in the thousand of pages in the Bible, it is nowhere mentioned that "God" taught anyone a language.
The authorship of most of the books of the Bible is unknown. There were hundreds of tales circulating in those times about the coming of a Messiah, who would be called "Emmanuel", a name that no one called Jesus during his rather short three year preaching period.
The Messiah was suppose to be a spiritual and military leader, like a reincarnation of King David, or more specifically, the mythical vision of a King David.
If the Hebrews were the Chosen People, then why was the New Testament written in Aramaic, the language that nearly all the Jews in Palestine spoke? Or at least Hebrew, which was also written like Aramaic, with the same alphabet?
I called "this character" your God because, your "character" in no way, shape nor form is my God nor the God that wrote scripture, created the universe nor formed mankind. I also disagree with you that "the authorship of most of the books of the Bible is unknown", while they may be unknown to you they are widely known in the Bible.
Many people referred to Jesus by many names, Messiah, Rabbi, teacher, Savior of as you referred to Him as a "Character". I don't speak fluent Greek, Aramaic nor Hebrew so, I don't get hung up on what people called him.
Many Jewish leaders wanted a king, a leader, a military leader or a force to be reckoned with. Jesus clearly stated that was NOT why He came. The secular leaders of the day were also very fearful that Jesus would usurp their political power and that the people would follow Jesus instead of them. Many of the so-called "leaders" were making their living off of stealing money from those they considered their underlings, peasants, slaves, etc.
I don't know where you got the notion that the "Hebrews" were the chosen people. Clearly scripture tells us that the Jews were the chosen people. Salvation is freely available to non-Jews but, the "chosen people" are of Jewish ancestry. Just like today, there are/were people who didn't follow, worship or serve the Lord. Some of those people are gentiles and some of those people are Jews.
As far as the Bible not telling us specifically about God teaching anyone, the Bible clearly states that not all of what God/Jesus did is contained in scripture. There are many mysteries of God that are not contained in scripture, that does not mean that they didn't happen. There is clear scriptural evidence that Jesus did teach the disciples MUCH. The Holy Spirit continues to comfort and teach believers to this day as scripture clearly tells us.
The writer's of scripture were human beings. Just because all of scripture is "God breathed" does not mean that scripture was written in a language that was unfamiliar to the writer's. As scripture tells us, God through the Holy Spirit instructed human beings to write down certain things and then those human beings wrote them down, using their own language. Nowadays we have numerous translations of what they wrote down. There is even one passage in the gospels that tells us that if all the acts of Jesus were written down that it would fill volumes.