The whole book is about courage and faith. The people are told they will be given the land, but only once they start walking to claim it. For 40 years they walked around in circles, now they have to walk into the land they have been promised, and claim it in faith.
Over and over the book shows how God miraculously keeps his promises to his people; from stopping the River Jordan from flowing, to causing the walls of Jericho to fall down. God blesses His people, and keeps his promises. This faithfulness is what prompts Joshua to quip the famous line "
...if serving the Lord seems undesirable to you, then choose for yourselves this day whom you will serve, ... But as for me and my household, we will serve the Lord.” (Joshua 24:15)
He gave us the land we walk
My house serves the Lord
