Numbers 10
“When you arrive in your own land and go to war against your enemies who attack you, sound the alarm with the trumpets. Then the Lord your God will remember you and rescue you from your enemies. Blow the trumpets in times of gladness, too, sounding them at your annual festivals and at the beginning of each month. And blow the trumpets over your burnt offerings and peace offerings. The trumpets will remind the Lord your God of his covenant with you. I am the Lord your God.”
"They marched for three days after leaving the mountain of the Lord, with the Ark of the Lord’s Covenant moving ahead of them to show them where to stop and rest. As they moved on each day, the cloud of the Lord hovered over them. And whenever the Ark set out, Moses would shout, 'Arise, O Lord, and let your enemies be scattered! Let them flee before you!'. And when the Ark was set down, he would say, 'Return, O Lord, to the countless thousands of Israel!'