Sahih Muslim Book 32, Hadith Number 6332.

Chapter : He who goes in the mosque or in the bazaar or a place of gathering like it with a weapon should see that the spearhead does not harm anyone.

Jabir b. Abdullah reported that a person happened to come to the mosque with arrows and their iron-ends were exposed, so he was commanded that he should grasp the pointed heads so that these might not do any harm to a Muslim.