The Israelites were entering the Promised Land, led by Joshua after Moses their longtime leader had died. They battled five Amorite kings at the same time and, in a massive victory, conquered the combined Amorite armies. Joshua told the people, "Do not be afraid, nor be dismayed; be strong and of good courage, for thus the LORD will do to all your enemies against whom you fight" (Joshua 10:25).
This was almost verbatim what the Lord had told Joshua when he was inaugurated as leader of the people of Israel: “No one will be able to stand up against you all the days of your life. As I was with Moses, so I will be with you; I will never leave you nor forsake you. Be strong and courageous, because you will lead these people to inherit the land I swore to their forefathers to give them” (Joshua 1:5-6).
From this we see that Joshua fully believed the words that he heard from the Lord and had integrated that prophetic promise into his life, to the degree that he spoke it out to those he was leading. I think there is a lesson in this. We also need to hear from the Lord through prayer, Bible study, rhema words, and our conscience, to the degree that it becomes evident in our lives that we are living out the word spoken over us. Then we are to take from what God has told us and share it with others. The courage and encouragement Joshua received from the Lord he shared with the rest of God’s people. In the same way, we can share testimonies from things we have overcome in our lives and promises God has spoken to us to encourage others.
Thankfully, we are not called to physical warfare as the Old Testament Israelites were when they were clearing the land promised to Abraham from those that inhabited it. This is made extremely clear in Scripture: “The weapons we fight with are not the weapons of the world. On the contrary, they have divine power to demolish strongholds. We demolish arguments and every pretension that sets itself up against the knowledge of God, and we take captive every thought to make it obedient to Christ” (2 Corinthians 10:4-5). But we are nevertheless in a very real war. In fact, the warfare we wage is all the more difficult because it is a spiritual war and it is often hard to realize the battles we are facing. We need to be strong and courageous, just as Joshua and the Israelites needed to. And we have the opportunity and responsibility to encourage one another in this struggle with the words and promises God has given us. Encouragement is a powerful weapon—let us all learn how to use it well!