COMMENTARY on 41:13
A. Yusuf Ali:

Translation:
But if they turn away, say you: "I have warned you of a stunning Punishment (as of thunder and lightning) 4479 like that which (overtook) the ´Ad and the Thamud!"
Commentary:

4479  See verse 17. below.

 

Muhammad Asad:

Translation:
BUT IF they turn away, say: 16 “I warn you of [the coming of] a thunderbolt of punishment 17 like the thunderbolt [that fell upon the tribes] of Ad and Thamud!” 18
Commentary:
16  This connects with the opening sentence of verse 9 above: "Would you indeed deny Him who has created…", etc.
17  See note 40 on 2:55.
18  For the story of these two ancient tribes, see 7:65-79 and the corresponding notes in particular 48 and 56; also 26:123-158.