Surah An-Nisa, Verse 18

وَلَيۡسَتِ ٱلتَّوۡبَةُ لِلَّذِينَ يَعۡمَلُونَ ٱلسَّيِّـَٔاتِ حَتَّىٰٓ إِذَا حَضَرَ أَحَدَهُمُ ٱلۡمَوۡتُ قَالَ إِنِّي تُبۡتُ ٱلۡـَٰٔنَ وَلَا ٱلَّذِينَ يَمُوتُونَ وَهُمۡ كُفَّارٌۚ أُوْلَٰٓئِكَ أَعۡتَدۡنَا لَهُمۡ عَذَابًا أَلِيمٗا١٨

walaysati l-tawbatu lilladhīna yaʿmalūna l-sayiāti ḥattā idhā ḥaḍara aḥadahumu l-mawtu qāla innī tub'tu l-āna walā alladhīna yamūtūna wahum kuffārun ulāika aʿtadnā lahum ʿadhāban alīman

But repentance is not [accepted] of those who [continue to] do evil deeds up until, when death comes to one of them, he says, "Indeed, I have repented now," or of those who die while they are disbelievers. For them We have prepared a painful punishment.