I adore this entire psalm. There's a rawness that everyone can relate too. Essentially some of David's friends, who David considered very close, turned on him.
In verse 3 we see that his friends bore a grudge against David, but there doesn't seem to be any attempt for resolution. Instead we see - added to the grudge - oppression, fraud, and ruin (v. 10-11).
Understandably David is hurt. So hurt that he wishes destruction over them (v 15)... haven't we all been there? Who would be so emotionally hurt that they want physical retribution? Me and David, at the very least; I have a suspicion we aren't alone.
There's a key difference David and us - David could have gotten vengeance. He had some pretty beefy, sword-capable men that followed him. But he didn't. Instead he did what? Queue the verse:
Evening, Morning, and Noon - he sought the Lord. David prayed. He surrendered his problems, constantly, consistently, and never taking matters in his own hands.
Make it personal
Is there strife between you and another in your life? How are you handling it? How does that compare to what David did?
Do you struggle with believing that praying over the same thing multiple times is weakness or won't work? Journal about why you feel this way, and ask God to help you see things His way.
Why is it so hard to surrender issues like this to God? Why does it benefit you to do so?