Mercy means God not giving us what we do deserve (the punishment for our sin), while grace is God giving us what we don’t deserve (the gift of eternal life).
Although God is merciful, He is also a God of justice. His statement, “The soul that sins must die” still applies (Deut 24:16; Ezek 18:4,20; Rom 6:23). We are doomed by our wrongdoing and deserve punishment, yet God, in His mercy, has provided a way of escape from sin’s penalty through Jesus who died in our place (Ps 103:2-4,8; Isa 53:11). Mercy is shown to all who repent, believe and in humility plead, “God be merciful to me a sinner” (Lk 18:13). We are justified freely and so have peace with God (Rom 3:24, 5:1). It is because of His great mercy we are saved, He wants all people to be saved (Eph 2:4,5; Tit 3:5; 2 Pet 3:9).
We, who have experienced mercy because God has forgiven us so much, in turn are blessed if we show mercy, and in fact if we do not extend the mercy of forgiveness to others we will not be forgiven by God (Mt 5:7, 6:12,14,15). Therefore, it is in our best interest to do to others, as God has done to us.
In the measure you have received mercy from God, give it to others
God is the father of mercy, and this is revealed to generations who fear Him (Lk 1:50; 2 Cor 1:3). David said, “To the merciful you Lord, show yourself merciful” (Ps 18:25).
Jesus was moved with compassion and exhorts us to be merciful as God, our father in heaven, also is merciful...put on compassion (Mt 18:21-35; Lk 6:36; Eph 4:32; Col 3:12; Jas 2:13). David said, “Let me fall into hands of the Lord, for His mercy is very great; but do not let me fall into the hands of men” (1 Chr 21:13). He knew God was fair, whereas man can be exceptionally unjust.
The Bible declares, God decided to love Jacob and hate Esau. “Is God unjust? Not at all! For He says, ‘I will have mercy on whom I have mercy, and I will have compassion on whom I have compassion.’ It does not, therefore depend on man’s desire or effort, but on God’s mercy” (Mal 1:2,3; Rom 9:13-18). The words ‘love’ and ‘hate’ are used in a comparative sense, just as our love for our parents should be as hate when compared to our devotion to Him (Lk 14:26). God loves everyone with a merciful love and grace, however He has a unique relationship with believers and especially, “If you obey my commands, you will remain in my love, just as I have obeyed my Father’s commands and remain in His love…You are my friends if you do what I command” (Jn 15:10,14). Because of our devotion to Him, He reciprocates in a greater measure of love.