Musnad Ahmad 308:5

Hajjaj and Abu Kamil narrated to us, they said: Layth—meaning Ibn Sa'd—narrated to us, he said: Sa'id ibn Abi Sa'id narrated to me, from Abu Shurayh al-Adawi, that he said: My ears heard and my eyes saw when the Messenger of Allah (may Allah bless him and grant him peace) spoke, and he said: "Whoever believes in Allah and the Last Day, let him honor his neighbor. And whoever believes in Allah and the Last Day, let him honor his guest with his prize." They said: "And what is his prize, O Messenger of Allah?" He said: "A day and a night. And hospitality is three days, so whatever is beyond that is charity for him." And he said: "Whoever believes in Allah and the Last Day, let him speak good or remain silent." And Abu Kamil said: "And he should not stay with him until he causes him embarrassment."