When David went out to fight Goliath, he was offered King Saul’s armor, but refused it. It didn’t fit, and would have slowed him down. If he had been going to fight the giant only in his own strength, he definitely would not have attempted it without something to protect his body. But David’s armor was spiritual, much like Jesus’ sustenance at the Well of Sychar (John 4) . Armed with the word of God, the Holy Spirit’s power, the breastplate of righteousness, the belt of truth, and with his feet ready to take him to proclaim God’s truth, he had what he needed. David was filled with indignance at the taunts of those who “dared to defy the armies of the living God”(1 Samuel 17:26), and with the Holy Spirit of God, Who led him to victory.