Novel with time travel, religious references, main character being called "Gog," aliens, and pre-missing-link humanoids. Likely from 1980s

Question

I remember reading this book as a pre-teen or early teenager, and it seemed a bit old at the time. I was born in 1983, so it was likely written in the mid-'80s or earlier, but that is a guess. Definitely early '90s at the latest if it was brand new. I believe it had been in the Young Adult section of the library I'd checked it out from, but it may have just been in the fiction section, as I seem to recall reading it around the same time as some of the Pern novels, and I think those were in Fiction, not Young Adult.

Memory is a bit hazy on the details, beyond a present-day male scientist travelling to the prehistoric past, and early humanoids existing. While there, and trying to figure out a way home, the traveler discovered aliens, who had apparently visited Earth during that time period. Spent a good portion of time interacting with one of the early humanoids. Discovered the aliens were, essentially, the "missing link" between them and the next evolution that eventually led to humanity as we know it, though I can't remember if it was via experimentation or breeding with the Earth population.

Other things that have stuck in my mind are a wheel-within-a-wheel, which the traveller recalls seeing mention of in the bible, and sees an alien vehicle or device that fits that description. While trying to communicate with the early humanoid, the traveler ends up being called "Gog," and for some reason that I can't recall realizes this humanoid is essentially calling him a god, or "the" God, unsure which. There seemed to be several biblical-related connections between the events of this past time that the traveler noted to himself. Unfortunately, any part of the title or author eludes me, as well as additional plot-related details beyond the traveler trying to return home.

Answer 1

Although I can't find a copy of the book to confirm it, this sounds very like the book Gods or Demons? by A. M. Lightner, which has been asked about before in Time travelers meet prehistoric ancestors and discover they are being taught or herded or are the children of aliens

Kirkus describes the book as:

Mad inventor Eliphat Digges, his brother Tom and a stereotypically dumb female/nurse named Sadie are jolted back some 10,000 years in a time machine accident only to find the Middle Eastern Desert populated by three different races -- Neanderthals, an aggressive colony of star travelers who have passed themselves off as gods, and homo sapiens (the result of interbreeding between the other two). The discovery should be a mind blower, but as Eliphat busies himself repairing the machine and Tom and Sadie happily acquire a Neanderthal slave and barter a pocketknife for native artifacts, the scene begins to look like a cross between first generation TV sci-fi and the Ugly American. In a word, silly.

The book was published in 1973 so it fits with the time you remember it. Sadly it is long out of print and copies are hard to find. Perhaps if anyone can find a copy they can confirm it matches the points you remember.