Nehemiah 4:16-18

From that day on, half of my men did the work, while the other half were equipped with spears, shields, bows and armor. The officers posted themselves behind all the people of Judah who were building the wall. Those who carried materials did their work with one hand and held a weapon in the other, and each of the builders wore his sword at his side as he worked. But the man who sounded the trumpet stayed with me.