It was narrated that Abu Hurairah said:
"The Messenger of Allah said: 'Your Lord wrote for Himself with His Own Hand before He created the creation: "My mercy precedes My wrath." (RU)
English reference (RU): Vol. 1, Book 1, Hadith 189 (RU)
Arabic reference (RU): Book 1, Hadith 194 (RU)