You don't send me to jail. In fact, you give me the bike plus a hundred dollars. That is grace. Justice, which demands payment, does not meet the requirement of mercy, which seeks forgiveness. Mercy does not meet the requirement of justice.
Grace meets both.
The Lamp Analogy Let's say I am at your house or apartment with my wife. We are talking about church and in my zeal I accidentally knock over your lamp. Now, this lamp is special. A dear friend gave it to you and it is has great sentimental value, and besides, you need a light in your room. After a moment or two you realize that the damage is done and decide to forgive.