How do we know our righteousness comes from faith in Christ?

Philippians 3:9 delineates a crucial distinction in Paul’s theology; he states, 'not having mine own righteousness, which is of the law, but that which is through the faith of Christ, the righteousness which is of God by faith.' This passage underscores that our righteousness cannot stem from our attempts to uphold the law but is entirely reliant on faith in Christ. The righteousness we receive is imputed to us by God, reflecting His grace and mercy. Thus, knowing this provides assurance of salvation and a firm foundation for our faith, affirming that we cannot earn God’s favor through works.