> One of the primary themes of Deuteronomy, however, is that YHWH is the only God. It shows up most obviously in places like Dt. 4 (at the beginning) and here in Dt. 32.39 (at the end). There are plenty of verses through Deuteronomy that speak of other "gods," but they are portrayed as non-deities, false ideas, and not really gods at all, though that is the term used for them.
this is pretty common ancient near eastern monolatry, yes. it's a hyperbolic way of affirming the sovereignty of the primary deity.
compare:
See, then, that I, I am He;
There is no god beside Me.
I deal death and give life;
I wounded and I will heal:
None can deliver from My hand.
deuteronomy 32:39:
Unique one, like whom among the gods?
Goodly bull of the Ennead,
Chief of all the gods,
Lord of Truth, Father of the gods,
Who made mankind, who created the flocks,
Lord of what exists, who created the tree of life,
hymn to amun-ra. maybe deuteronomy goes a bit further, but it's not really until deutero-isaiah that we start to get rejections of the other gods as fakes, products of human hands.
> Part of the problem with this is the recognition by scholars Deuteronomy as a whole has the elements of a 2nd millennium international treaty, and therefore seems (by that standard) to have been produced by a single author in a single time to achieve his literary and theological purpose.
under the wellhausen/friedman varieties of the documentary hypothesis, deuteronomy is a singular document, yes. we have reasons to think that's not quite the case, of course, and that's not counting the places that are obvious quotes of older sources (where the author says he's quoting older sources) like this part.
i'm not really sure what "as a whole has elements" means. it clearly does have some elements, yes, of ancient treaties. but so do the texts it's based on, the commandment portions of J and E. "has features of an old text" doesn't really indicate a text is old, since, well, we could just copy old texts we have now. the book of mormon has some features of 1600's english texts, but it was clearly written in the 1800's. we can tell this because it misuses some of those features, and includes theology clearly derived from the 1800's revivalist movements.
and we can do the same thing with detueronomy; the book of kings tells us of a major theological and political shift following the discovery of an unknown book in the temple. those shifts are all motivated by features unique to deuteronomy. so the book was probably deuteronomy.
> Yes, but as I said, it is used as a euphemism for YHWH,
yes, it most frequently is. but it doesn't appear to be here, based on the immediate context. "elyon" is a generic honorific for the most high god, and for nearly all of the biblical period, that god was yahweh. there are hints, however, that prior to the biblical period el and yahweh would have been distinct. during that period, el would have been elyon at first, and then yahweh would have taken over, precisely as we see with baal. there are hints, like psalm 82, that this is exactly what happened.
oh, since i cribbed the hymn to amun-ra from here, i think you may be interested in this:
http://religionatthemargins.com/2011/07/the-most-heiser-yahweh-and-elyon-in-psalm-82-and-deuteronomy-32/