And Allah the Exalted said (in Surah Aal-e-Imran) «ومن يغلل يأت بما غل‏» "And whoever betrays, he will bring that which he betrayed with him on the Day of Resurrection."

Narrated Abu Huraira: The Prophet got up amongst us and mentioned Al Ghulul, emphasized its magnitude and declared that it was a great sin saying, "Don't commit Ghulul for I should not like to see anyone amongst you on the Day of Ressurection, carrying over his neck a sheep that will be bleating, or carrying over his neck a horse that will be neighing. Such a man will be saying: 'O Allah's Apostle! Intercede with Allah for me,' and I will reply, 'I can't help you, for I have conveyed Allah's Message to you Nor should I like to see a man carrying over his neck, a camel that will be grunting. Such a man will say, 'O Allah's Apostle! Intercede with Allah for me, and I will say, 'I can't help you for I have conveyed Allah's Message to you,' or one carrying over his neck gold and silver and saying, 'O Allah's Apostle! Intercede with Allah for me,' and I will say, 'I can't help you for I have conveyed Allah's Message to you,' or one carrying clothes that will be fluttering, and the man will say, 'O Allah's Apostle! Intercede with Allah for me.' And I will say, 'I can't help you, for I have conveyed Allah's Message to you."