The Psalmist is confident in the presence of God: there is no malice in him. In that, the Psalmist resembles Job. No matter what befell him, "Job did not sin nor did he say anything disrespectful of God."
Can we be so confident in the presence of God? We can indeed, but in an entirely different way. We can stand confidently before God, not because we are sinless, but because we are forgiven.
Our Christian confidence before God is not self-confidence. Our confidence is based on God's mercy. Our confidence is that hope which, with faith and love, determines our stance before God. Through His passion, death and resurrection, Jesus won for us the grace to be able to stand unafraid in the presence of God. We can thus stand, not because we are totally sinless, but because we are sinners who by grace can entrust our lives to God and His mercy.
Because God loved us by sending His Son, we can be sure that God will never be against us. God will always be on our side, not indeed to affirm that we have never sinned but that our sins are forgiven in Christ Jesus.
Father, we have sinned before You. Confident of Your mercy, we open our hearts to Your forgiving love.