Abu Hurairah (RA) 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).
Related hadith on this topic
Explanation & Benefits
Shaykh Maulana Abdul Aziz Alvi
Hadith Commentary: Benefits and Issues: From this hadith, it is understood that to point a weapon at one’s brother, whether to frighten him or merely in jest to disturb him, is a cause for the angels’ curse. This proves that to trouble a Muslim brother, to cause him distress, is not the way of Muslims. Because sometimes a weapon, even unintentionally, can become a cause of harm, therefore, in order to prevent this, the Shariah has declared even gesturing with it to be a crime. And today, instead of mere gestures, Muslims are targeting other Muslims with weapons.
Source: Tuhfat al-Muslim: Commentary on Sahih Muslim, Page: 6666