The Quran

فَإِذا مَسَّ الإِنسانَ ضُرٌّ دَعانا ثُمَّ إِذا خَوَّلناهُ نِعمَةً مِنّا قالَ إِنَّما أوتيتُهُ عَلىٰ عِلمٍ ۚ بَل هِيَ فِتنَةٌ وَلٰكِنَّ أَكثَرَهُم لا يَعلَمونَ

Muhammad Asad

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 !"¹ Nay, this [bestowal of grace] is a trial: but most of them understand it not!

Lit., "knowledge" - i.e., "my prosperity is due to my own ability and shrewdness": see the first sentence of 28:78 and the corresponding note. But whereas there this "saying" or thought is attributed to the legendary Qarun, in the present instance - which is by far the earlier in the chronology of Qur'anic revelation - it is said to be characteristic of man as such (see, e.g., 7:189-190, where this tendency is referred to in connection with the experience of parenthood).