How do we know God's mercy is always saving?

God's mercy is described as always saving because it is extended sovereignly to those whom He has chosen. Ephesians 2:4 states, 'But God who is rich in mercy, for His great love wherewith He loved us, even when we were dead in sins, hath quickened us together with Christ.' This indicates that God's mercy acts decisively to save us from our sins, ensuring that everyone to whom He shows mercy is ultimately saved. It highlights that mercy is not an offer but an active demonstration of God's compassion towards the needy, affirming that His mercy leads to our salvation.