How do we know the concept of law and grace is true?

The distinction between law and grace is foundational in scripture and is clearly articulated in both the Old and New Testaments. Genesis 2 outlines the covenant of works through the command regarding the tree of the knowledge of good and evil, while the promise of salvation and life through faith in Christ represents the covenant of grace. Galatians 4 further reinforces this separation, illustrating the allegory of Hagar and Sarah as a representation of two covenants. The continuous message of scripture emphasizes that salvation is solely by grace, not through works.