Psalm 77 has been instructional and inspirational for me. It demonstrates that we can be open and honest with God; how the art of remembering God's grace in troubled times leads us out of those times; that God is truly with us even when we cannot see Him. Martin Luther offers these thoughts on Psalm 77:
The 77th psalm is a psalm of instruction. The psalmist uses himself as an example of how to find comfort when affliction comes and the conscience is troubled, as if God is angry with it. He says that he was so troubled that he could not have any sleep or even speak. But this comfort follows: The psalmist can fight off the thoughts with which he futilely suffered, and he can grasp instead the thought of the mighty works of god in the histories of old. Here we find that God's work was to help the miserable, the troubled, and the abandoned, and to throw down the self-secure, proud scoffer, for example , when he delivered the children of Israel from Egypt.
For this reason His paths are called "hidden." He is there to help when we think that we are totally abandoned. We should learn this well. God intends by this psalm to show us and teach us His manner of helping, namely that he never abandons us when things go ill. Instead, we should wait upon His help at that time with the greatest confidence and not believe our thoughts.
From "Reading the Psalms with Luther."