Deuteronomy 20:1-3

1“When you go out to war against your enemies and see horses, chariots, and an army larger than yours, do not be afraid of them, for the Lord your God, who brought you out of the land of Egypt, is with you.

2When you are about to engage in battle, the priest is to come forward and address the army.

3He is to say to them, ‘Listen, Israel: Today you are about to engage in battle with your enemies. Do not be cowardly. Do not be afraid, alarmed, or terrified because of them.