בראשית, פרק י״ט, פסוק ל״ה

The second night in the cave brought new psychological and practical hurdles for both Lot and his daughters. The daughters worried that their father would refuse to drink wine and become intoxicated again. To bypass his hesitation, they first served him other beverages. This lowered his guard, eventually leading him to consume the wine as well [העמק דבר].

A stark contrast emerged between the two sisters. While the older daughter had initiated their plan without shame or internal resistance, the younger sister felt deep pangs of conscience and a strong aversion to the shameful act. She was driven primarily by her older sister's influence. To go through with it, she had to summon a great deal of internal strength, physically and mentally rousing herself to act [העמק דבר, הכתב והקבלה].

Lot remained completely oblivious during the act itself due to his deep intoxication. However, much like the previous night, even though he was unaware while she lay with him, he did sense that something had occurred after she got up [צאינה וראינה]. His total lack of awareness was essential for the daughters' plan to succeed. Although relations with daughters were not strictly forbidden under the ancient laws given to the descendants of Noah, the people of that era had already established moral boundaries to distance themselves from such behavior. Had Lot been sober, he would never have consented [הכתב והקבלה].