In Psalm 143, David acknowledges that no one is righteous in God's sight and we have no right to claim justice from God on our own merits. The set of Psalms: 43, 93, and 143, are about going to God for justice on the basis of relationship, because of his love and mercy for his. That he alone saves.

http://raisedtowalk.org/r43

More on Reading through the Psalms
http://raisedtowalk.org/psalms

Passages from the World Messianic Bible