Sahih Bukhari Volume 008, Book 073, Hadith Number 029.

Narated By Abu Huraira : I heard Allah's Apostle saying, Allah divided Mercy into one-hundred parts and He kept its ninety-nine parts with Him and sent down its one part on the earth, and because of that, it’s one single part, His creations are Merciful to each other, so that even the mare lifts up its hoofs away from its baby animal, lest it should trample on it."

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