Lost in the Recording

I've always wondered - there are massive sections of narrative and events, not to mention thoughts and feelings (when they are rarely discussed if at all) that are obviously left out of the Torah.  We know nothing of Moshe's life in between fleeing from Egypt and the burning bush, other than a few scant details. Perhaps most memorably, we know absolutely nothing of the 38 years of "wandering" that is barely addressed in Bemidbar - not a single word is mentioned other than the change in populations throughout that time as captured in this parasha.

So, my interest is always piqued when a verse, a phrase, even a word, from a later (or earlier?) event fills in the details of what happened or will happen.

Take for example, Bemidbar 25:6, in which "the burnt offering that is continual, that was done at Mount Sinai..."

Now, I certainly am not a Torah genius who has the entire book memorized.  But when I read this, I didn't seem to recall any specific mention of a burnt offering "at/on Mount Sinai."  I flipped back to Yitro and, at least in the climactic sections of the giving of the Torah, there is no mention of korbanot.  So, at least if taken literally, I cannot - and do not think it exists - any collection of offerings on Mount Sinai.

What we need to remember, however, is what I began with - since obviously everything cannot be captured, things must have happened that were not written down, perhaps even a burnt offering atop Sinai, as seemingly implied here.

This stands in nice comparison to the story of Zelophchad's daughters - which we just read about a few verses ago - and how they demanded that a similar halachic gap be filled in (or else injustice would result).

It's true that everything is contained in Torah.  But what if everything, and then some, were contained, and it was "up to us" to figure out that "and then some."  Everywhere I look, I keep seeing untold hints of flexibility, interpretation, demand for change, and progression/evolution in the Torah.  It gives new and much deeper meaning to a phrase I never really liked or, quite frankly, understood, which is "the Living Torah."  Are there still things which are non-negotiables?  Sure.  But I don't think it was ever intended that being a Torah-observant, deeply-engaged Jew would be so incredibly stringent to the exclusion of so many and so much.  And a brief reference to something that, well, didn't explicitly happen (as far as I remember and am aware), provides the tiniest pinhole of interpretative opening to go so far as to say that.