The Messenger of Allah ﷺ said, "My example and the example of the prophets before me is like that of a man who built a house and made it beautiful and elegant, except for the place of one brick in a corner. People began to walk around it admiring it and saying, 'Why was this brick not placed?' I am that brick, and I am the seal of the prophets."
أن رسول الله ﷺ قال: إن مثلي ومثل الأنبياء من قبلي، كمثل رجل بنى بيتا فأحسنه وأجمله إلا موضع لبنة من زاوية، فجعل الناس يطوفون به ويعجبون له ويقولون: هلا وضعت هذه اللبنة؟ قال: وأنا اللبنة، وأنا خاتم النبيين.
Bukhari narrated it in Manaqib (3535), and Muslim in Fadail (2286:22), both citing Qutayba bin Saeed, who said, "Ismail bin Jafar narrated to us, from Abdullah bin Dinar, from Abu Salih, from Abu Hurairah," and he related the hadith.Imam Ahmad narrated it (7322) from Sufyan, from Abu Zinad, from Araj, from Abu Hurairah, relating it in similar fashion, except that it contains, "except for this gap, for I am that gap."Muslim also narrated it through this same route, except that in it he mentioned it in the same way as the first route, that is, "the brick.""The gap" (with a damma) refers to the opening left by something broken or torn down, meaning except for this spot where there is a gap in the structure.