Mercy is God withholding the just punishment of sin from those who deserve it. While grace lavishes on; mercy puts off, or holds back. God’s mercy is propelled into motion by His love: “But God, being rich in mercy, because of His great love with which He loved us (Eph 2:4). The love of God—His goodness in action—moves Him to not give us what we deserve. This mercy, not our goodness or works, is what leads to our regeneration, salvation, and justification: “He saved us, not on the basis of deeds which we have done in righteousness, but according to His mercy, by the washing of regeneration and renewing by the Holy Spirit, whom He poured out upon us richly through Jesus Christ our Savior, so that being justified by His grace we would be made heirs according to the hope of eternal life” (Titus 3:5-7), and causes the new birth: “Blessed be the God and Father of our Lord Jesus Christ, who according to His great mercy has caused us to be born again to a living hope through the resurrection of JesusChrist from the dead” (1 Pet 1:3).
The Apostle Paul put himself forward as an illustration of one who was rescued from spiritual blindness and the tragic consequences of unbelief by the mercy of God and for the glory of God. “And yet for this reason I found mercy, in order that in me as the foremost, Jesus Christ might demonstrate His perfect patience, as an example for those who would believe in Him for eternal life” (1 Tim 1:16); “…even though I was formerly a blasphemer and a persecutor and a violent aggressor. And yet I was shown mercy, because I acted ignorantly in unbelief” (1 Tim 1:13). The conversion of any sinner is sheer mercy.