Musnad Ahmad 32:1597

Mu'ammal narrated to us, Hammad narrated to us, Thabit narrated to us, from Anas, that the Prophet, peace and blessings of Allah be upon him, said: "There is no Muslim who dies and four people from the households of his nearest neighbors testify for him, except that He (Allah) says: 'I have accepted your knowledge regarding him, and I have forgiven him for what you do not know.'"