The sympathy which exists between the mind and the body is very great. When one is affected, the other responds. The condition of the mind has much to do with the health of the physical system. If the mind is free and happy under a consciousness of rightdoing and a sense of satisfaction in causing happiness to others, it will create a cheerfulness that will react upon the whole system, causing a freer circulation of the blood and a toning up of the entire body. The blessing of God is a healer; and those who are abundant in benefiting others will realize that wondrous blessing in their hearts and lives.—Testimonies for the Church 4:60. MM 105.1