How do we know human righteousness is insufficient?

Human beings naturally tend to lean on their own understanding of righteousness, often believing that their good deeds can earn favor with God. However, Scripture is clear that all have sinned and therefore, no one can stand justified in God's sight based on their personal merit. The way of man appears right in his own eyes, yet it leads to death (Proverbs 14:12). This underscores the vital truth that true righteousness comes only through faith in Jesus Christ, who fully met the requirements of God's law. As believers, we need to constantly remind ourselves that we cannot achieve righteousness on our own; instead, we must rely solely on Christ's redemptive work.