The Holy Quran 4:39 — Surah An-Nisa
Arabic text
وَمَاذَا عَلَيْهِمْ لَوْ ءَامَنُوا۟ بِٱللَّهِ وَٱلْيَوْمِ ٱلْـَٔاخِرِ وَأَنفَقُوا۟ مِمَّا رَزَقَهُمُ ٱللَّهُ ۚ وَكَانَ ٱللَّهُ بِهِمْ عَلِيمًا
Translation
What harm (loss) will it do them (the Kuffaar) if they believe in Allaah and the Last Day and spend of that which Allaah had provided for them? (It will do them only good to do this, otherwise terrible harm will befall them for remaining as Kuffaar. Furthermore, it is Allaah Who gives them the wealth they have.) Allaah is Ever Aware of them (and will punish them for their kufr and misdeeds).
Tafsir (excerpt) — Tafsir Usmani
That is, these disbelievers would have suffered no loss had they, instead of disbelief, believed in Allah and the Day of Resurrection, and, instead of miserliness and showing off, spent their wealth in the way of Allah; on the contrary, it would have been pure gain for them. The harm lies in what they are choosing.
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