Rashi on Genesis 19:1/רש"י על בראשית י״ט:א׳

1שני TWO — One to destroy Sodom, the other to rescue Lot — it was he who had come to heal Abraham — whilst the third, who had come to make the announcement to Sarah, had departed as soon as he had carried out his mission (Midrash Tanchuma, Vayera 8).

2המלאכים ANGELS — But elsewhere (Genesis 18:2) Scripture calls them men! When the Divine Presence was with them, it speaks of them as men. Another explanation is: in connection with Abraham whose power to receive heavenly visitors was great and whom angels visited as regularly as men, it calls them men, but in connection with Lot it calls them angels (Genesis Rabbah 50:2).

3בערב AT EVENTIDE — Did it, however, take the angels such a long time to travel from Hebron to Sodom? But they were angels of mercy and so they tarried — perhaps Abraham would succeed in his advocacy for them (Genesis Rabbah 50:1).

4ולוט ישב בשער סדום AND LOT WAS SITTING IN THE GATE OF SODOM — The word is written without a ו so that it may be read יָשַׁב (he sat) — because that day they had appointed him as their judge (Genesis Rabbah 50:3).

5'וירא לוט וגו AND LOT SAW THEM etc. — From the practice in Abraham’s house he had learned to look out for strangers (Genesis Rabbah 50:4).