בראשית יט:יא פירוש: רש״י, רשב״ם, ספורנו ורד״ק

פתח THE DOOR (literally, opening) — This means the hollow space (opening) through which people go in and out.

בסנורים, a plague of blindness.

וילאו למצוא הפתח, even though they had already been smitten with blindness they did not therefore desist from their wicked intention. This is in line with the psychological insight of our sages in Eyruvin 19 that the wicked will not become penitents even when they stand at the gates of hell. [the Nazis persisting in the “final solution,” even while already defeated by the Russsians are the best example of this insight we know of. Ed.]