Modern doctors and psychiatrists agree with what Christian Science has been proclaiming to the world for over seventy-five years, namely that negative and morbid thinking has a bad effect on the body. But there the agreement ends. The modern physicist agrees that matter is materially mental, but Christian Science teaches that matter is unintelligent and therefore not truly substantial.
Christian Science is religious Science, distinct and entirely separate from all humanly mental processes of healing. In "Miscellaneous Writings" Mary Baker Eddy shows the danger of using human will power as a cure and points to the divine power, which heals spiritually. She says (p. 59): "Having no true sense of the healing theology of Mind, you can neither understand nor demonstrate its Science, and will practise your belief of it in the name of Truth. This is the mortal 'mind-cure' that produces the effect of mesmerism. It is using the power of human will, instead of the divine power understood, as in Christian Science; and without this Science there had better be no 'mind-cure,'—in which the last state of patients is worse than the first."
The teaching of this Science educates a student not only in examining and analyzing thoughts, but in replacing these thoughts with spiritual qualities, the energies of Truth and Love. While the one practicing "mind-cure" may lovingly admonish a patient to watch his thought and keep out fear, self-condemnation, criticism, and other negative thoughts, this may make the patient more aware of these thoughts. It is difficult to destroy what one definitely holds as real. One of the rules for salvation which Christ Jesus gave to the world in his Sermon on the Mount is (Matt. 5:8), "Blessed are the pure in heart: for they shall see God." Jesus also said (Matt. 6:22), "If...thine eye be single, thy whole body shall be full of light."