Somewhat in the spirit of Job, David starts this psalm asking why and how long the Lord will hide His face, allowing His servant to experience sorrow while his enemies are exalted over him. He then goes on to pray for God to consider him and enlighten his eyes before his enemies prevail against him. Finally, though, he offers up this praise:
5 But I have trusted in Your mercy;
My heart shall rejoice in Your salvation.
6 I will sing to the Lord,
Because He has dealt bountifully with me.
David, as we have seen before, has gone through terrible times of distress and attack. He is human. He has struggled with the thoughts of defeat and isolation. He feels the pressure, so he speaks out, even against God. However, after the venting has passed, David goes back to the truth that he knows: God is faithful, and can be trusted. When you are in dire consequences, and do not have hope in yourself, hope in the Lord. He is trustworthy and right. He will always deal bountifully with you.