In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
Abu Bakrah [radiyallaahu-anhu] said that Allaah’s Messenger [sallal laahu alayhi wasallam] said, “If a Muslim point a weapon at his Muslim brother, an Angel of Allaah continues cursing him until he turns it away from him”.
In this hadeeth there is a clarification regarding the danger of carrying weapons in the midst of the Muslims- in their gatherings and in the Masaajid. It poses great danger to the Muslims during disputes, for indeed anger can lead one to point a weapon at his brother due to personal [disagreements] and it can be due to something trivial, so it leads him to a pit of the hell fire- either due to killing his brother or injuring him. And due to this, the Prophet [sallal laahu alayhi wasallam] issued a serious warning regarding weapons and [a warning] against pointing a weapon at a Muslim.
It is not permissible to point a weapon at a Muslim even out of jesting. It is not permissible- in all situations – to point a weapon at a Muslim brother even out of jesting due to the fact that it will frighten him. The aim is that if one carries a weapon, it is obligated on him to carry it safely, otherwise there is no need to carry weapons in Muslim countries. And the prohibition becomes more emphasised during personal disputes and differing, so a person should not carry a weapon, for indeed anger leads a person to commit evil and shaytaan does entice a person to commit evil. In this hadeeth, it has been stated that pointing a weapon at a Muslim is a major sin due to the fact that the angels curse the one who points a weapon at his Muslim brother.
[Source: At-ta’leeqaat Al-Maleehah Alaa Silsilah Al-Ahaadeeth As-Saheehah. Vol 1. Page 56. slightly paraphrased]