God commands believers to be strong and courageous, and not to be afraid or discouraged, because He will always be with them. The document provides examples from the Bible where God performed mighty acts, such as parting the Red Sea and feeding multitudes with few resources, to illustrate that He is capable of handling any situation. It concludes by emphasizing that God is "big enough" for anything and reminds readers to follow His instruction to be brave with His presence and help.