Blessed are the merciful,
for they will be shown mercy.
-Matthew 5:7
Mercy is a natural step in the Beatitudes of Jesus as we turn from the citizenry requirements of the kingdom of heaven as people who love God with all of their heart, soul and strength. Through poverty of spirit, mourning over sin, choosing to submit to the will of God and seeking His righteousness we now are ready to turn to the second part of the Great Command, loving our neighbors. Like God, we love by extending mercy to all with a purity of heart that allows us to become peacemakers who accept persecution for the sake of righteousness and because of Christ.
To illustrate the power of God’s mercy moving through us to others Jesus told a parable about a man who owed a great debt to his king but could not repay (Matthew 18:21-35). As the king was sentencing the debtor to prison the man pleaded for mercy. Being merciful, the king forgave the debt and let the man go free.
However, no sooner had the one who received mercy from the king left he soon found a fellow citizen who owed him a comparatively insignificant amount. However, rather than extending the mercy he had received to the one who owed him money he chose rather to choke him and have him thrown into prison because he could not repay the debt immediately.
Seeing the actions of the unmerciful man, the king’s servants reported what they had observed and they brought him back to the king. “‘You wicked servant,’ he said, ‘I canceled all that debt of yours because you begged me to. Shouldn’t you have had mercy on your fellow servant just as I had on you?’” was the king’s question to the man (vss. 32-33) whereupon the king rescinded his mercy and cast the debtor into prison. At the conclusion of the parable Jesus makes the point crystal clear:
“This is how my heavenly Father will treat each of you unless you forgive your brother or sister from your heart” (vs. 35). God’s mercy is never to be hoarded but distributed freely as He distributes sunshine and rain on the just and unjust alike (Matthew 5:44-45).
MERCY AND GRACE
John Stott makes a distinction between Grace and Mercy that is 
helpful. Grace is pardon for sin and its condemnation while Mercy is compassion for sin’s consequences and its victims that leads to cure, healing and help (Christian Counterculture).
Grateful for mercy kingdom people are merciful not out of fear of losing the gracious gifts of their Father. The motivation is the bottomless well or mercy that has been extended to them. It compels them to pass along the blessing. Why? Because, having meekly submitted their will to their Father and because of their craving His righteousness they strive to be like Him, imitating Him (Luke 6:36).
ATTITUDE OF GRATITUDE
A point of distinction between true kingdom people and those who are not is not measured by how much they attend church or how many great works they do (Matthew 7:21-23). Rather, how they treat others out of gratitude for the mercy that has been extended to them is a critical consideration. As James says: “Mercy triumphs over judgment” (James 2:13).