Mercy shown is evidence of mercy received. (Source unknown)
When you see someone who is gracious and kind to others, you are probably seeing a person who himself has been granted mercy and kindness. As someone else has written, “Our deeds of mercy are evidence of God’s grace.” To live with a sense of peace and to live peaceably with others will often require a demonstration of grace and forgiveness.
There will be no mercy for those who have not shown mercy to others. But if you have been merciful, God will be merciful when he judges you (James 2:13).