Overall meaning : When Abraham realised who his guests were, he asked them, ‘What is the serious mission on which Allah has sent you?’ They replied, ‘We have been sent to a wicked, unbelieving people (the people of Lot) to rain down upon them stones of baked clay that are specially marked by your Lord for those who have transgressed His limits.’
First We brought forth all the believers who were in the city. We did not find there anyone who surrendered themselves to Us but a single household (Lot and his family, with the exception of his wife), and We left in that city a sign testifying to the dreadful fate its people suffered—as a lesson for those who fear Allah’s punishment to learn from it.