Genesis 19:34 is a verse most readers speed past. Targum Pseudo-Jonathan slows down and lets us hear the elder daughter plan.
"And it was the day following, and the elder said to the less, Behold, now, I lay my evening with the father; let us make him drink wine this night also, that he may be drunk; and go thou and lie with him, that we may raise up sons from our father."
The Aramaic preserves a chilling element the English translation only hints at: the elder admits, openly and without shame, what she did the night before. "I lay my evening with the father." She is not apologizing. She is reporting, and she is organizing.
The phrase "that we may raise up sons from our father" — in Aramaic, u-n'qayyem zar'a me-abuna — is the daughters' stated purpose throughout this whole episode. They believe they are the remnant of the human race and that their cave is Noah's ark. In their minds, they are not committing incest. They are saving humanity.
The rabbis of the Talmud (Horayot 10b) made a striking observation. The elder daughter openly names her son Moab — "from the father" — while the younger daughter will soften the name of her son to Ben-Ammi — "son of my people." The elder had no shame; the younger still had some. And because of that difference, later Jewish law would treat the two peoples differently — Moabites excluded more harshly, Ammonites somewhat less (Deuteronomy 23:3-6).
The rabbis were not excusing either sister. They were reading the Torah's moral fingerprints carefully.
The takeaway: the way you name what you have done is already part of the judgment that follows.