How do we know salvation is by God's mercy and not our works?

In Romans 15:9-10, Paul articulates that God's overarching purpose in salvation is the glorification of His mercy. The emphasis on mercy highlights that no one can claim salvation through personal merit or efforts. The scriptures consistently affirm that we are saved by grace alone (Ephesians 2:8-9), and that this grace is given freely to the unworthy. The doctrine of salvation based on God's mercy aligns with the historic Reformed perspective, which maintains that human works contribute nothing to one's standing before God. Instead, we are completely dependent on the redemptive work of Christ, who fulfills every promise of God regarding salvation.