Abu Hurayra reported that the Messenger of Allah, may Allah bless
him and grant him peace, said, "If any of you makes an oath and swears
in his oath by al-Lat and al-'Uzza should say, 'There is no god but Allah.'
If any of you tells him companion, 'Come on, I will make a bet with you'
should give sadaqa."
Rabi'a ibn 'Abdullah ibn al-Hadir ibn 'Abdullah reported tht two
men wagered two cocks in the time of 'Umar. 'Umar ordered that the cock
be killed and a man of the Ansar said to him, "Will you kill a something
which glorifies Allah?" So 'Umar left it.
Husayn ibn Mus'ab reported that someone told Abu Hurayra, "We
wager two pigeons and we do not want for there to be a third unwagered
pigeon between them so that the unwagered pigeon might take the winnings."
Abu Hurayra said, "That is how children behave. You are at the point where
you should abandon that."