The children of Israel had a day every 7 years called the day of release, or the day of pardon. It was given to them to act as a type or shadow of the grace and mercy that Christ so freely offers us. But is is also given to remind us the importance of freely forgiving all the people in our lives. To recognize on allow the atonement of Jesus Christ to work for others and not just ourselves 

Packer- https://www.churchofjesuschrist.org/study/general-conference/1977/04/the-mediator?lang=eng