حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا أَبُو خَالِدٍ الأَحْمَرُ، عَنْ هِشَامٍ، عَنْ مُحَمَّدٍ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم ‏"‏ أَنَّ امْرَأَةً بَغِيًّا رَأَتْ كَلْبًا فِي يَوْمٍ حَارٍّ يُطِيفُ بِبِئْرٍ قَدْ أَدْلَعَ لِسَانَهُ مِنَ الْعَطَشِ فَنَزَعَتْ لَهُ بِمُوقِهَا فَغُفِرَ لَهَا ‏"‏ ‏.‏

Abu Huraira reported Allah's Messenger (may pace be upon him) as saying: A prostitute saw a dog moving around a well on a hot day and hanging out its tongue because of thirst. She drew water for it in her shoe and she was pardoned (for this act of hers). Translation Not Available

Book reference: Sahih Muslim Book 39 Hadith 5578
Web reference: Sahih Muslim Book 26 Hadith 2245 a