A. Yusuf Ali:Translation:
Now, when trouble touches man, he cries to
Us: 4318 But when We bestow a favour upon
him 4319 as from Ourselves, he says, "This has been
given to me because of a certain knowledge (I
have)!" 4320 No, but this is but a trial, but most of
them understand not!

Muhammad Asad:Translation:
NOW [thus it is:] when affliction befalls man, he cries out unto Us for help; but when We bestow upon him a boon by Our grace, he says [to himself], “I have been given [all] this by virtue of [my own] wisdom!” 55 Nay, this [bestowal of grace] is a trial: but most of them understand it not!
4318 Cf. 30:33 and n. 3545.
4319 Cf. 39:8 above.
4320 Cf. 28:78, and n. 3408. Prosperity may be a trial as much as adversity.