Here's what Robert Alter has to say about the opening of Genesis 19:
1. came into Sodom at evening, when Lot was sitting in the gate. The whole episode is framed in an elegant series of parallels and antitheses to Abraham's hospitality scene at the beginning of chapter 19. Both men are sitting at an entrance - the identical participial clause with the same verb - when the visitors appear. Lot's entrance is the city gate: he can sit "in" it because Canaanite cities had what amounted to a large chamber a the gateway; here people gathered to gossip, to do business, and above all to conduct justice; the gate would have given on the town square, the area referred to by the messengers in verse 2. There is an antipodal thematic distance from tent flap to city gate, as the narrative quickly makes clear. Abraham's visitors, moreover, arrive at midday, where as Lot's visitors come as darkness falls - a time when it is as dangerous to be out in the streets of Sodom as in those of any modern inner city.
2. turn aside. Lot resembles his uncle in the gesture of hospitality. He uses the verb "turn aside" (sur) instead of Abraham's "go on past" ('avar) because unlike the solitary tent in the desert, there are many habitations here, in addition to the public space of the square.
set off early. This may merely be merely to emphasize that he will not delay them unduly, but it could hint that they can depart at daybreak before running into trouble with any of the townsfolk.
3. a feast...flatbread. Perhaps an ellipsis is to be inferred, but this is a scanty looking "feast." In contrast to Abraham's sumptuous menu, the only item mentioned is the lowly unleavend bread (matsot) of everyday fare, not even the loaves from fine flour that Sarah prepares.
4-5 the men of the city, the men of Sodom...We are the men. Throughout this sequence there is an ironic interplay between the "men" of Sodom, whose manliness is expressed in the universal impulse to homosexual gang rape, and the divine visitors who only seem to be "men."
8. I have two daughters who have known no man. Lot's shocking offer, about which the narrator, characteristically, makes no explicit judgement, is too patly explained as the reflex of an ancient Near Eastern code in which the sacredness of the host-guest bond took precedence over all other obligations. Lot surely is inciting the lust of the would-be-rapists in using the same verb of sexual "knowledge" they had applied to the visitors in order to proffer the virginity of his daughters for their pleasure. The concluding episode of this chapter, in which the drunken Lot unwittingly takes the virginity of both his daughters, suggests measure-for-measure justice meted out for his rash offer.
for have they not come under the shadow of my roof beam? This looks like a proverbial expression for entering into someone's home and so into the bonds of the host-guest relationship. But "roof-beam" implies a fixed structure and so accords with the urban setting of Lot's effort at hospitality; Abraham, living in a tent, in the parallel expression in his hospitality scene, merely says, "for have you not come by your servant?"
9. came as a sojourner ... sets himself up to judge! The verb "to sojourn" [which, for what it's worth, in french is translated étranger] is the one technically used from resident aliens. "Judge," emphatically repeated in the infinitive absolute (wayishpot shafot), picks up the thematic words of judge and just from God's monologue and His dialogue with Abraham in Chapter 18.
That's as far as Derrida goes with the story ... he then jumps (deceptively, if you ask me) to Judges 19, which is it's own can of worms, and I can throw out some commentary on that, if we'd like. But I think these comments are interesting and would love to see what people hermeneutically do with them.
