What does the Bible say about the prayer of a righteous man?

In James 5:16, we find the profound truth that the prayer of a righteous person is powerful and effective. This reflects the importance of a life lived in accordance with God’s will, whereby one's prayers are backed by a sincere heart and a right standing before God. Christ Himself illustrates this in Luke 18:13-14, contrasting the self-righteous Pharisee with the humble publican. The latter’s plea, 'God, be merciful to me, a sinner', captures what it means to approach God in genuine humility and reliance on His mercy rather than on one’s own works.