Why is it important to understand Christ's righteousness?

The sermon contrasts human efforts to achieve righteousness through religious practices with the perfect and complete righteousness provided by Christ. Just as one cannot patch an old garment with new cloth, our methods of righteousness cannot supplement Christ's perfect righteousness. The righteousness of Christ is described as a new garment that covers us completely, an essential aspect of salvation. When believers recognize their need for true righteousness, they can rejoice in the grace offered through Christ, which fulfills the law on their behalf (Matthew 9:16-17).