Sayyiduna Anas (may Allah be pleased with him) narrates this saying of the Prophet (peace and blessings be upon him): "Whoever believes in Allah Almighty and the Last Day should honour his guest, and whoever believes in Allah Almighty and the Last Day should speak good or else remain silent."
Imam al-Bazzar recorded it. Its chain contains a narrator, Muhammad bin Thabit al-Bunani, and he is da'if (weak).