Sunan Ibn Majah, Book 33, Hadith 30 (In-Book) ⓘ
It was narrated that Suraqah bin Ju'shum said: "I asked the Messenger of Allah about a lost camel that comes to my cisterns that I have prepared for my own camels - will I be rewarded if I give it some water to drink? He said: Yes, in every living being there is reward.'"
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا عَبْدُ اللَّهِ بْنُ نُمَيْرٍ، حَدَّثَنَا مُحَمَّدُ بْنُ إِسْحَاقَ، عَنِ الزُّهْرِيِّ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ جُعْشُمٍ، عَنْ أَبِيهِ، عَنْ عَمِّهِ، سُرَاقَةَ بْنِ جُعْشُمٍ قَالَ سَأَلْتُ رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ عَنْ ضَالَّةِ الإِبِلِ تَغْشَى حِيَاضِي قَدْ لُطْتُهَا لإِبِلِي فَهَلْ لِي مِنْ أَجْرٍ إِنْ سَقَيْتُهَا فَقَالَ " نَعَمْ فِي كُلِّ ذَاتِ كَبِدٍ حَرَّى أَجْرٌ " .
also referenced under: Hadith 3686 (Reference) & Volume 5, Book 33, Hadith 3686 (DarusSalam)