All those gathered here will know that it is not by sword or spear that the Lord saves; for the battle is the Lord's, and he will give all of you into our hands.
1 Samuel 17:47 NIV
David had complete trust and confidence in the Lord. It was not unfounded; he had seen the Lord give him courage and strength against bears and lions while shepherding his flock. Yet David had faith that the Lord would continue to be with him, just as he had been in the past, even in spite of a situation that was dire.
Even better is that David didn't quietly trust in the Lord but leave room to save face. He proclaimed his trust in the Lord to everyone, both friend and foe. He left no room for doubt, because he let his faith hang out in public view.
Draw on what the Lord has done to continue to have confidence in the Lord. Don't be bashful in a way that is resulting from doubt, but rather fully trust in the Lord and proclaim my trust in Him so that His name will be glorified.
Lord, I trust in You. My confidence is in You, my Refuge and my Strength. You alone deserve glory and honor and praise, and I give it all to You. Thank you for working powerfully through the lives of Your servants. Let me see Your hand at work today and always as I take part in Your battles. I love you!