As Joshua is to succeed Moses and continue the conquest, Moses charged Joshua not to fear the physical kingdoms of Canaan, for the Lord, the invisible God, fights for him. Joshua will need to trust in the Lord and his work. This command was previously given to the people (e.g., Deuteronomy 1:21).
22 Ne les craignez point; car l'Eternel, votre Dieu, combattra lui-même pour vous.