How do we know that Jesus Christ's righteousness is revealed in the gospel?

The righteousness of God is revealed uniquely in Jesus Christ, who embodies God's perfect obedience. As noted in the sermon, Christ's life demonstrates obedience to God's commandments, decrees, and law, showcasing true righteousness. Furthermore, His sacrificial death on the cross serves as a punitive capital punishment, which not only fulfills the righteous demands of God but also provides a way for the ungodly to be justified. Therefore, through Christ's work, the heart of the gospel declares how God's righteousness upholds justice while extending grace.