Musnad Ahmad 788:93

'Affan narrated to us, Hammad narrated to us, Thabit informed us, from Abu Burdah, from Abu Musa, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "If one of you passes through a mosque, a marketplace, or a gathering, and he has arrows in his hand, let him hold them by their heads [the blades]." Abu Musa said: "By Allah, we did not die until some of us pointed them at the faces of others."