The Prophet ﷺ said, "When one of you passes through our mosque or our marketplace carrying arrows, let him hold the arrowheads firmly in his hand, lest he injure any of the Muslims with them," or he said, "let him grasp the arrowheads."
ى، عن النبي ﷺ قال: إذا مر أحدكم في مسجدنا، أو في سوقنا، ومعه نبل، فليمسك على نصالها بكفه، أن يصيب أحدا من المسلمين منها بشيء أو قال ليقبض على نصالها.
Bukhari narrated it in Fitan (7075), and Muslim in Birr wa Silah (2615:24), both through routes from Abu Usama, from Buraid, from Abu Burda, from Abu Musa, who related it.His saying, "the blades" is the plural of "blade," which is the iron part of a spear, an arrow, or a knife.