Justification by Faith
God declares sinners righteous based on Christ's work received through faith alone.
Justification is God's legal declaration that guilty sinners are righteous, based not on their performance but on Christ's perfect righteousness credited to their account. Paul contrasts Abraham, justified by faith before circumcision, with those who seek justification through law-keeping. The law reveals sin but cannot save; faith receives the righteousness God provides. This doctrine brings peace with God, ending the futile attempt to earn acceptance. Justification is courtroom language, not medical: dikaioō means to declare righteous, not to make well.
Therefore, since we have been justified through faith, we have peace with God through our Lord Jesus Christ.
Thomas Aquinas distinguished between initial justification (God's act) and ongoing sanctification (progressive transformation), both works of grace.
Epistle to the Romans