This peace that Jesus promises is about a sense of wholeness, contentment, and fulfilment even amidst the conflict and strife that comes with living in the world. This peace is a gift of God, but can only be experienced when we give over to God our desire to control everything in our lives. What might you need to give over to God to experience that kind of peace?
In prayer, offer those situations or issues to God and resist the urge to pick them back up later.