Musnad Ahmad 31:81

Abu Mu'awiyah narrated to us, Al-A'mash narrated to us, from Abu Salih, from Abu Sa'id al-Khudri, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "My likeness and the likeness of the prophets before me is like the likeness of a man who built a house, and he completed it, except for one brick. So I came, and I completed that brick."