Regret

فَبَعَثَ ٱللَّهُ غُرَابًا يَبْحَثُ فِى ٱلْأَرْضِ لِيُرِيَهُۥ كَيْفَ يُوَٰرِى سَوْءَةَ أَخِيهِ ۚ قَالَ يَـٰوَيْلَتَىٰٓ أَعَجَزْتُ أَنْ أَكُونَ مِثْلَ هَـٰذَا ٱلْغُرَابِ فَأُوَٰرِىَ سَوْءَةَ أَخِى ۖ فَأَصْبَحَ مِنَ ٱلنَّـٰدِمِينَ

God sent a raven to scratch up the ground and show him how to cover his brother’s corpse and he said, ‘Woe is me! Could I not have been like this raven and covered up my brother’s body?’ He became remorseful.

فَتَرَى ٱلَّذِينَ فِى قُلُوبِهِم مَّرَضٌ يُسَـٰرِعُونَ فِيهِمْ يَقُولُونَ نَخْشَىٰٓ أَن تُصِيبَنَا دَآئِرَةٌ ۚ فَعَسَى ٱللَّهُ أَن يَأْتِىَ بِٱلْفَتْحِ أَوْ أَمْرٍ مِّنْ عِندِهِۦ فَيُصْبِحُوا۟ عَلَىٰ مَآ أَسَرُّوا۟ فِىٓ أَنفُسِهِمْ نَـٰدِمِينَ

yet you [Prophet] will see the perverse at heart rushing to them for protection, saying, ‘We are afraid fortune may turn against us.’ But God may well bring about a triumph or some other event of His own making: then they will rue the secrets they harboured in their hearts,

إِنَّ ٱلَّذِينَ كَفَرُوا۟ يُنفِقُونَ أَمْوَٰلَهُمْ لِيَصُدُّوا۟ عَن سَبِيلِ ٱللَّهِ ۚ فَسَيُنفِقُونَهَا ثُمَّ تَكُونُ عَلَيْهِمْ حَسْرَةً ثُمَّ يُغْلَبُونَ ۗ وَٱلَّذِينَ كَفَرُوٓا۟ إِلَىٰ جَهَنَّمَ يُحْشَرُونَ

They use their wealth to bar people from the path of God, and they will go on doing so. In the end this will be a source of intense regret for them: they will be overcome and herded towards Hell.

وَلَوْ أَنَّ لِكُلِّ نَفْسٍ ظَلَمَتْ مَا فِى ٱلْأَرْضِ لَٱفْتَدَتْ بِهِۦ ۗ وَأَسَرُّوا۟ ٱلنَّدَامَةَ لَمَّا رَأَوُا۟ ٱلْعَذَابَ ۖ وَقُضِىَ بَيْنَهُم بِٱلْقِسْطِ ۚ وَهُمْ لَا يُظْلَمُونَ

Every soul that has done evil, if it possessed all that is on the earth, would gladly offer it as ransom. When they see the punishment, they will repent in secret, but they will be judged with justice and will not be wronged.

قَالَ عَمَّا قَلِيلٍ لَّيُصْبِحُنَّ نَـٰدِمِينَ

and so God said, ‘Soon they will be filled with regret.’

فَعَقَرُوهَا فَأَصْبَحُوا۟ نَـٰدِمِينَ

But they hamstrung her. In the morning they had cause to regret it:

وَقَالَ ٱلَّذِينَ ٱسْتُضْعِفُوا۟ لِلَّذِينَ ٱسْتَكْبَرُوا۟ بَلْ مَكْرُ ٱلَّيْلِ وَٱلنَّهَارِ إِذْ تَأْمُرُونَنَآ أَن نَّكْفُرَ بِٱللَّهِ وَنَجْعَلَ لَهُۥٓ أَندَادًا ۚ وَأَسَرُّوا۟ ٱلنَّدَامَةَ لَمَّا رَأَوُا۟ ٱلْعَذَابَ وَجَعَلْنَا ٱلْأَغْلَـٰلَ فِىٓ أَعْنَاقِ ٱلَّذِينَ كَفَرُوا۟ ۚ هَلْ يُجْزَوْنَ إِلَّا مَا كَانُوا۟ يَعْمَلُونَ

The oppressed will say to them, ‘No, it was your scheming, night and day, ordering us to disbelieve in God and set up rivals to Him.’ When they see the punishment, they will fall silent with regret, and We shall put iron collars on the disbelievers’ necks. Why should they be rewarded for anything other than what they have done?

يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوٓا۟ إِن جَآءَكُمْ فَاسِقٌۢ بِنَبَإٍ فَتَبَيَّنُوٓا۟ أَن تُصِيبُوا۟ قَوْمًۢا بِجَهَـٰلَةٍ فَتُصْبِحُوا۟ عَلَىٰ مَا فَعَلْتُمْ نَـٰدِمِينَ

Believers, if a troublemaker brings you news, check it first, in case you wrong others unwittingly and later regret what you have done,