(60) باب بَيَانِ الْوَسْوَسَةِ فِي الإِيمَانِ وَمَا يَقُولُهُ مَنْ وَجَدَهَا
It is narrated on the authority of Abu Huraira that the Messenger of Allah (ﷺ) observed:
People will constantly ask you questions pertaining to knowledge till they would say: Allah created us, but who created Allah? he (the narrator) says: he (Abu Huraira) was (at the time of narrating this hadith) catching hold of the hand of a man and he said: Allah and the Messenger told the truth. Two persons have already put me this question, and this is the third one, or he said: One man has put me this question and he is the second one.
Reference: Sahih Muslim 135 a
In-book reference: Book 1, Hadith 254
USC-MSA web (English) reference(deprecated numbering scheme): Book 1, Hadith 246