Tafsir of Ad-Dhariyat 51:31

"He said, 'What is your business...'" When he [Abraham] knew they were angels, and that they do not descend except by the permission of Allah as messengers for certain matters, he asked, "What is your affair and what do you seek?"

"...with the criminal people?" Meaning the people of Lot.

"Stones of clay" He means al-sijjil (baked clay), which is clay cooked just as bricks are cooked, until it becomes as hard as stone.

"Marked" (musawwamah) Meaning designated/marked. It is derived from al-sumah, which is a sign. Upon each one of them was the name of the person to be destroyed by it. It is also said: they were marked to indicate they were stones of punishment. It is also said: they bore a sign indicating they were not from the stones of this world.

He called them "transgressors" (musrifin), just as he called them "transgressors" (‘adin), because of their excess and hostility in their deeds, as they were not content with what was permitted to them.

"In it" The pronoun refers to the town [Sodom], even though it was not explicitly mentioned, because it was understood.

"Therein" This is evidence that faith (iman) and submission (islam) are one, and that both are attributes of praise.

It is said: They [the believers] were Lot and his two daughters. It is also said: Lot and his household who were saved were thirteen. Qatadah said: If there had been more than that in it, He would have saved them, so that it may be known that faith is protected and its people are not lost in the sight of Allah.

"A sign" A mark by which those who fear [Allah] take heed, unlike those whose hearts are hardened. Ibn Jurayj said: It is a layered rock [remaining] in it. It is also said: It is black, foul-smelling water.

"And in Moses, when We sent him to Pharaoh with a clear authority. But he turned away with his forces and said, 'A sorcerer or a madman.' So We took him and his soldiers and cast them into the sea, while he was blameworthy."