How do we know that we cannot be righteous on our own?

Scripture makes it clear in Romans 3:23 that 'all have sinned and fall short of the glory of God,' establishing the universal need for righteousness that is unattainable through human effort. Our sinful nature, inherited from Adam, renders us incapable of perfect obedience to God's law, which is the standard for righteousness. This theme is echoed throughout the Bible, as seen in Isaiah 64:6, where our righteous acts are compared to 'filthy rags' in the sight of a holy God.

The failure of Israel, particularly after King David, serves as a historical example of this principle. Their repeated acts of rebellion and idolatry illustrate humanity's inability to maintain a righteous standing before God without divine intervention. God, knowing our plight, promises a righteous branch to save us, emphasizing that it is not by our works but by grace through faith that we receive righteousness. This teaching affirms the core belief in sovereign grace that righteousness is entirely sourced in Christ.