Sayyiduna Zayd bin Khalid (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; whoever believes in Allah and the Last Day should speak good or else remain silent; and hospitality is for three days, whatever is beyond that is charity."
Imam al-Bazzar and Imam al-Tabarani recorded it, and the narrators of Imam al-Bazzar are the narrators of the Sahih.