Christian Science is practical. It operates quickly and effectively when it is understood and correctly applied. It can be stated very simply, but its application to the human problem is not always so easy.
The basis of Christian Science is the First Commandment (Ex. 20:3), "Thou shalt have no other gods before me." Our Leader, Mary Baker Eddy, says in the textbook, "Science and Health with Key to the Scriptures" (p. 340): "The First Commandment is my favorite text. It demonstrates Christian Science." The allness of God, infinite Spirit, the perfection of the real man, Spirit's image and likeness, and the consequent nothingness of matter and evil—these truths constitute a logical explanation of the First Commandment. These simple truths, understood and applied, demonstrate Christian Science. Some individuals gain spiritual understanding quickly and others more slowly, but to those who are ready to accept the fact that God, Spirit, is All-in-all a great spiritual illumination comes. In Deuteronomy we read (4:35), "The Lord he is God; there is none else beside him."
When a student of Christian Science began reading the textbook, the truth of what God is and of man's oneness, or unity, with Him was eagerly and easily grasped. She could not see, however, how thinking of God and the real man could produce any change upon her body. How could thoughts, which are mental, affect what seemed to be an object, called the material body? One day a severe pain, the result of a sharp turn of an ankle, was almost instantly healed when she remembered a statement heard at a Wednesday testimony meeting in a Church of Christ, Scientist.