Sahih Muslim Book - 2, Hadith - 677

حَدَّثَنِي أَبُو سَعِيدٍ الْأَشَجُّ وَأَبُو كُرَيْبٍ مُحَمَّدُ بْنُ الْعَلَاءِ وَإِسْحَاقُ بْنُ إِبْرَاهِيمَ قَالَ إِسْحَاقُ أَخْبَرَنَا وَقَالَ الْآخَرَانِ حَدَّثَنَا وَكِيعٌ حَدَّثَنَا الْأَعْمَشُ قَالَ سَمِعْتُ مُجَاهِدًا يُحَدِّثُ عَنْ طَاوُسٍ عَنْ ابْنِ عَبَّاسٍ قَالَ مَرَّ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ عَلَى قَبْرَيْنِ فَقَالَ أَمَا إِنَّهُمَا لَيُعَذَّبَانِ وَمَا يُعَذَّبَانِ فِي كَبِيرٍ أَمَّا أَحَدُهُمَا فَكَانَ يَمْشِي بِالنَّمِيمَةِ وَأَمَّا الْآخَرُ فَكَانَ لَا يَسْتَتِرُ مِنْ بَوْلِهِ قَالَ فَدَعَا بِعَسِيبٍ رَطْبٍ فَشَقَّهُ بِاثْنَيْنِ ثُمَّ غَرَسَ عَلَى هَذَا وَاحِدًا وَعَلَى هَذَا وَاحِدًا ثُمَّ قَالَ لَعَلَّهُ أَنْ يُخَفَّفُ عَنْهُمَا مَا لَمْ يَيْبَسَا.

It was narrated that Ibn 'Abbas said: "The Messenger of Allah (s.a.w) passed by two graves, and he said: 'They are being punished, but they are not being punished for anything grave (i.e., it was not difficult to avoid). One of them used to walk around spreading malicious gossip, and the other did not protect himself from his urine.' He (s.a.w) called for a palm branch, split it in two, then planted one piece on one grave and the other on the other grave. Then he said: 'Perhaps it (the punishment) will be reduced for them so long as this does not dry out."'