God is his safe place. The One he runs to in times of trouble. He pleads with God, "have mercy on me" (vs. 10) for his foes have been unmerciful. He prays, "raise me up" and be the lifter of my head. The enemy wants him to believe his lies, but David knows better! He can hold his head up because he and God know they are not true. He may feel like his reputation is at stake, but instead of justifying himself to those that are against him, he turns to God and trusts Him to secure his reputation. He is the only One who can right the wrongs.
David also asks for God's mercy so "that [he] may repay them" (vs. 4). He asks the LORD for opportunity to show his enemies that he is walking in forgiveness and harbouring no malice toward them. He desires to repay the evil with good. David is a man who strives to live life with integrity, even in the midst of strong adversity.
When I am thought or spoken of poorly, I have learned to first check my heart. I ask God to examine it and show me "if there is any offensive way in me" (Psalm 139:24). I ask Him to reveal to me if I've done something wrong, so I can quickly make it right. If I find that my heart is clean and my motives were pure, I forgive the one(s) speaking against me and take my situation to the LORD, asking Him to be my Vindicator and the healer of my hurting heart. He is my Defender, the One who clears my name and upholds my reputation. My response to adversity should always be integrity.
Father, thank You for the peace that walking with integrity brings. Thank You that even though we are sometimes wronged, You have the power to make things right. Thank You Lord that we don't have to please the world; we need only live to please You. In Jesus' name I pray, amen.