How do we know that justification comes by faith and not by works?

In Galatians, the Apostle Paul emphasizes that a person is not justified by the works of the law but through faith in Jesus Christ (Galatians 2:16). He argues that if justification could come through the law, then righteousness would be by the law (Galatians 3:21). However, the law reveals our sinfulness and incapacity to save ourselves, leading us to rely on God's grace instead. This concept of being justified by faith is supported throughout the New Testament, where it is clear that only through trust in Christ do we receive righteousness and salvation.