(47) باب مَا يُؤْمَرُ بِهِ مِنَ الْقِيَامِ عَلَى الدَّوَابِّ وَالْبَهَائِمِ
Abu Hurairah reported the Apostle of Allaah(ﷺ) as saying " While a man was going on his way, he felt himself thirsty severely. He found a well and e went down in it. He drank water and came out. Suddenly he saw a dog panting and eating soil due to thirst. The man said (to himself) "This dog must have reached the same condition due to thirst as I had reached. So he went down into the well, filled his sock with water, held it with his mouth and came up. He supplied water to the dog. Allaah appreciated this and forgave him." They asked "Apostle of Allaah(ﷺ), Is there any reward for us for these beasts? He replied, For every cool liver there is a reward."
Reference: Sunan Abi Dawud 2550
In-book reference: Book 15, Hadith 74
English translation: Book 14, Hadith 2544