Mike, as I see it, the NT writers probably never even heard of the name YHVH, didn’t know Hebrew and presumed that the LXX renderings were “all she wrote” (to use an Alabama expression). It *was* their scripture, just as, for a millennia, the Vulgate *was* the Bible to Christianity. It wasn’t a “translation” in their minds. If it was in the LXX, then “it is written in the scriptures.” They never dreamed of consulting a Hebrew source. So, since the divine name had been expunged, it was not any part of their thoughts.

My view of the history goes like this:

* in the earliest texts, God is “EL” and “ELOHIM” (the plural);
* God reveals his personal name as “YHVH”:

Gen 4:26 And to Seth, to him also there was born a son; and he called his name Enos: then began men to call upon the name of the LORD.

This was big in the Hebrew text.

* God issued a curse if anyone should take his name unworthily:

Exo 20:7 Thou shalt not take the name of the LORD thy God in vain; for the LORD will not hold him guiltless that taketh his name in vain.

* Jews thought it better to be safe than sorry, and avoid using the name outside of worship. “Lord” is used as a euphemism (but the text is not changed);

* Someone non-Hebrew-speaking entity creates the LXX in Alexandria. Some group uses it as its scriptures. (It is wrong to presume that these were mainstream Jews, though that is possible).

* this group knows only the translation, “lord”, and not the ineffable name. They think it refers to God’s “job” or “role” rather than as a stand-in for his name;

* Paul declares that God has temporarily conferred his role as lord onto a man, because of his obedience. Now God is known as “the father.” Jesus is now “the lord.”

* in the future, God will come to the Middle East and resume being lord directly and Jesus will step down and be just another man again.

All of this NT stuff has nothing to do with Jews, Judaism or the Hebrew scriptures. There, there is only YHVW, pronounced or not pronounced, as “lord” or “adonai” etc.

What all of this means is that we have a progression, not a static situation.

As for the NT, I think you’re right that all we see is kurios. My understanding is that in the oldest copies of the LXX, on the other hand, we see the actual Hebrew letters YHWH written out amid the Greek. (I don’t know a lot about these early copies. Can someone fill in details?)

At any rate, I don’t know when the change from YHWH to adonai and kurios took place, but it seems that the focus changed from the letters themselves to God. I suspect that this progression is more relevant for the history of writing than for theology, which might be way we don’t see any reflection of it in the NT. If so, it’s probably a mistake on our part to read too much into YHWH versus adonai today.

”
Gen 15:2
3 tn The Hebrew text has אֲדֹנָי יֱהוִה (‘adonay yehvih, “Master, LORD”). Since the Tetragrammaton (YHWH) usually is pointed with the vowels for the Hebrew word אֲדֹנָי (‘adonay, “master”) to avoid pronouncing the divine name, that would lead in this place to a repetition of אֲדֹנָי. So the Tetragrammaton is here pointed with the vowels for the word אֱלֹהִים (‘elohim, “God”) instead. That would produce the reading of the Hebrew as “Master, God” in the Jewish textual tradition. But the presence of “Master” before the holy name is rather compelling evidence that the original would have been “Master, LORD,” which is rendered here “sovereign LORD.”
”

I don’t understand a word of this. Whence do they get the word “LORD”?

We don’t know for sure that they mimicked the pointing from adonai, but one fact in particular points in that direction: Sometimes YHWH is pronounced elohim (Gen 15:2, for example), and when it is, the pointing is taken from elohim.

My follow-up question has to do with the New Testament. Its writers never seem concerned with a YHWH/Kurios distinction (whether quoting from the Hebrew or the LXX) in the way that English translators are concerned with the YHWH/Adonai distinction in the OT. That is, the NT writers seem to write as if there was nothing but Kurios or Adonai in the OT. Why is this?

And of course, the pointing took place late.. 7th? 11th century?