It is narrated from Sayyiduna Mu'awiyah bin Haydah (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "Allah Almighty created one hundred mercies. He placed one mercy among His creation, through which they show mercy to one another, and He has stored up ninety-nine mercies for His friends (awliya)."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17055