If one seated in a stationary railway train looks at a moving train on an adjoining track, the stationary train seems to be moving. By looking away from the moving train to some landmark, he becomes aware of the illusion.
In a similar manner corporeal sense seems to testify that the material world is the reality of being, that its activity is the fact of being. But through the earnest study of Christian Science one is able to look at that which is fixed, unchanging—God, the divine Principle of all real activity—and thus rise superior to the illusions of material sense. As one accepts the true nature of God as all-harmonious Spirit, infinite Life, he is able to understand that what material sense testifies to is not really what is going on.
The warfare between Spirit and flesh is the conflict between the true testimony of spiritual sense and the false testimony of material sense. We are saved from error and its effects through accepting the true testimony and rejecting the false.