How do we know that God shows mercy to the undeserving?

The assurance of God's mercy toward the undeserving is foundational to Reformed theology, as seen in biblical narratives such as that of Mephibosheth. Despite being disabled and having a lineage that could warrant his death, Mephibosheth is liberated from fear and death through David's compassion. This corresponds to God's grace in our lives—He does not treat us as our sins deserve (Psalm 103:10) but instead extends mercy, allowing us to sit at His table. Additionally, passages like Ephesians 2 affirm that we were dead in sin but made alive in Christ, underscoring that mercy is a divine gift bestowed without merit, confirming the character of God as gracious and merciful towards sinners.