Joy and Peace

It has been said that "Peace without Joy is contradictory." For the non-believers joy is peripheral while sorrow is primary. Why? It is said that this is so because for the non-believer the fundamental questions in life are unanswered while the peripheral questions are answered. For the christian joy is primary while sorrow is peripheral. It is said that this is so because for the christian the fundamental questions of life are answered while the peripheral questions may not be. Joy, therefore, comes from the peace we the believers have in Christ.