Anas ibn Malik said, "The Messenger of Allah, may Allah blesshim and grant him peace, said, 'People will continue to ask about thingsthat do not exist to such an extent that they will say, "Allah createdeverything, so who created Allah?"'" (FR)
English reference (FR): Book 55, Hadith 1286 (FR)
Arabic reference (FR): Book 1, Hadith 1286 (FR)