Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates that the Prophet (peace and blessings of Allah be upon him) said: "When Allah Almighty created the creation, He wrote in His Book what He made obligatory upon Himself, and that writing is placed above the Throne (and in it is written): 'Indeed, My mercy prevails over My wrath.'"
(Imam Ibn Hibban, may Allah have mercy on him, says:) The statement of the Prophet (peace and blessings of Allah be upon him): "It is placed above the Throne," relates to the expressions used by the Arabs in their idioms, although what is meant is 'under the Throne,' not 'above the Throne.' Just as Allah Almighty says: "Behind them is a king," what is meant is 'ahead of them is a king,' for if he were behind, those people would have already passed by. Its example is the saying of Allah Almighty: "Indeed, Allah is not ashamed to set forth the example of a mosquito or what is above it (as an example)," meaning what is less than a mosquito.