Mysticism, immediate, direct, intuitive knowledge of God or of ultimate reality attained through personal religious experience. Wide variations are found in both the form and the intensity of mystical experience. The authenticity of any such experience, however, does not depend on the form but solely on the quality of life that follows the experience. A mystical life is characterized by enhanced vitality, productivity, serenity, and joy as the inner and outward aspects harmonize in union with God.