Al-Fadil ibn Muslim reported that his father said, "When 'Ali,
may Allah be pleased with him, went out through the Bab al-Qasr, he saw
some backgammon players. He took them and locked them up from morning to
night. Some of them he only locked up for half the day. Those he locked
up until night were those who used silver. Those he locked up for half
the day were those who played it. He also commanded that they should not
be greeted."