How do we know that righteousness is by faith?

The doctrine of justification by faith alone is rooted in the example of Abraham, who believed God's promises and had righteousness credited to him. Romans 4:3 states, 'For what does the Scripture say? Abraham believed God, and it was accounted to him for righteousness.' This shows that righteousness is not based on personal merit but is given freely to those who trust in God's promises. Throughout the Scriptures, this principle of faith is confirmed repeatedly, encouraging believers to look to God for their justification.