This Psalm is another model of how to pray for help when we are at our human limit. The author knows he himself is not perfectly righteous, so he bases his prayer on God's mercy (2). He confesses how weak and crushed he feels (3-4). But he also strengthens his faith by remembering how God has helped him in the past (5).
We can strengthen ourselves for difficult times by seeking the word of God's unfailing love every morning (8), until it comes into our hearts. We also submit our lives to God's guidance and commit ourselves to be Jesus' disciples, learning his will.
Then we can experience God's leading on the pathway of life, and will experience true security, like we are walking on level ground (10). We gain assurance from our identity as God's servant (12).
Application: Father, thank you for your leading on my life. I want to seek your word every morning and learn to do your will as Jesus' disciple.
One Word: Lead me on level ground