Asking Permission
Bukhari :: Book 8 :: Volume 74 :: Hadith 314
Narrated Abu Huraira:
Allah's Apostle said, "Whoever among you takes an oath wherein he says, 'By Al-Lat and Al-'Uzza,' names of two Idols worshipped by the Pagans, he should say, 'None has the right to be worshipped but Allah; And whoever says to his friend, 'Come, let me gamble with you ! He should give something in charity. " (See Hadith No. 645)