Psa 3:3 For thou O Lord are a shield for me, the glory and the lifter of my head
Joshua fought many battles with God being His shield. God gave him a sneak preview of his life to come, “No man shall be able to stand before you all the days of your life. Just as I was with Moses, so I will be with you. I will not leave you or forsake you.” (Jos 1:5). God’s declaration of His presence in his life was the greatest difference maker of all. Similar to Moses with the rod of God (offensive weapon) in his hands to deliver Israel. Moses preferred God going with them as their shield than totally relying on the rod. God went before them by day as a cloud of wind and by night as a pillar of fire.
Chances of survival by shields (defensive) are greater than offensive weapons. David recognizing his total inability to make it apart from God armed himself with this truth, God is my shield, my glory and the lifter of my head. In Eph 6:16, believers are instructed above all things to take the shield of faith by which they will all be able to quench the fiery darts of the the wicked one. Prayer is the means by which we take the shield of faith, it is our way of inviting God to be to us what He was to David, Joshua, Abraham, Moses, men that trusted God to be their shield.