This foundational doctrine of the Reformation emphasizes that we are justified by God’s grace alone, through faith alone, in Christ alone. Unlike the Roman Catholic view, which sees justification as a process tied to sacraments and works, the Protestant understanding declares that justification is an act of God’s free grace. Through the imputation of Christ’s righteousness, sinners are pardoned and accepted as righteous in God’s sight. Rooted in Scripture (Ephesians 2:8-9, Galatians 2:15-16, John 14:6), this truth affirms that salvation is not earned but freely given through Christ’s perfect work. As Martin Luther proclaimed, we are "simul justus et peccator"—at the same time righteous and sinners. This teaching reminds us of the sufficiency of Christ and the unshakable assurance found in Him.