How do we know that God's righteousness is required for salvation?

The Scriptures reveal that God requires perfect holiness to stand before Him, as seen in Romans 3:23 and also echoed in Matthew 5:48, where we are told to be perfect as our heavenly Father is perfect. Since no one can achieve this standard through their works (Romans 7:18), the gospel presents Jesus Christ as the fulfillment of righteousness. He lived the perfect life we could not live and died the death we deserved, so that by faith in Him, we are clothed in His righteousness rather than our own flawed attempts.