Someone has offered this penetrating comparison of the difference between revenge, justice, and grace.
If someone brutally murders your son and you take things into your own hands, that's revenge.
If you're content to allow the law and the courts to arrest and punish the offender, that's justice.
But, if you pardon the murderer, adopt him, and take him home to live with you as your son, that's grace!
And that's exactly what God has done for you in Christ!
- unknown