Joy is a rare commodity.  It is not just a happy emotion; joy is the overwhelming gladness which stems from everything being right and expresses its energy in worship and godly activity (Romans 15:13).  It is the natural condition of heaven.  The 19thC pastor/evangelist, F B Meyer, wrote that ‘Joy is peace dancing; peace is joy at rest’.  Both are essential for spiritual health and only come from receiving forgiveness and new life from God, because of Christ’s atoning sacrifice through the indwelling Holy Spirit (Acts 2:38).