Sahih Muslim Book 32, Hadith Number 6336.

Chapter : The prohibition of pointing a weapon towards a Muslim.

Abu Huraira reported: Abu’l-Qasim (the kunya of Allah’s Messenger, may peace be upon him), said: He who pointed a weapon towards his brother the angels invoke curse upon him even if he is his real brother so long as he does not abandon it (the pointing of weapon towards one’s brother Muslim).