Sahih Adab al-Mufrad

It is narrated from Sayyiduna Abu Hurairah, may Allah be pleased with him, that he said: I heard the Messenger of Allah, peace and blessings be upon him, say: "Allah, the Mighty and Majestic, made mercy into one hundred parts. He kept ninety-nine parts with Himself and sent down only one part to the earth. It is because of this one part that people show mercy to one another, to the extent that a mare lifts its hoof so that it does not harm its foal."