From the very first chapter of Genesis, in which creation is declared to be of God and wholly good, there runs through the inspired pages of the Bible the insistent reiteration that God is good, and beside Him "there is none else." On page 469 of "Science and Health with Key to the Scriptures" by Mrs. Eddy, may be found the following statement: "The exterminator of error is the great truth that God, good, is the only Mind, and that the supposititious opposite of infinite Mind—called devil or evil—is not Mind, is not Truth, but error, without intelligence or reality.... We lose the high signification of omnipotence, when after admitting that God, or good, is omnipresent and has all-power, we still believe there is another power, named evil."
One of the idiosyncrasies of the human mind is the theory that there is an evil intelligence, law, and power. This theory Christian Science utterly repudiates, and through demonstration proves it to be an illusion. Power is that which causes, supports, and sustains,—never that which hinders, weakens, or destroys. Power is a characteristic of good; in the highest sense it is good, or God Himself. The theory of an evil intelligence or power that can make man sin or suffer without his own consent, is nothing but superstition, and has no more place in consciousness—the expression of God, good—than mistakes or errors have place in the consciousness of one who has a perfect understanding of mathematics. The demonstration of the omnipotence of good is based upon the distinction between reality and unreality, between the genuine and the false, and fulfills the Scriptural demand, "Be not overcome of evil, but overcome evil with good."
In the last analysis there are no mistakes. If a thing is not real it is not at all. There is no intermediary stage between the true and the false. Neither can the real be reversed. Whatever appears to be the reverse of Principle, good, actually is not at all, and must be entirely disowned and mentally reduced to nonexistence, in order that it no longer remain a seemingly conscious experience. This is illustrated in a sense of pain. Generally speaking, we have been taught to believe that pain is in the body; but Christian Science reveals the fact that pain is an erroneous mental sense, that is, it is mental in its nature; yet, since Mind is harmonious and sensationless, there really is no pain; and as this mental or spiritual reality is clearly perceived, the painful sense disappears in presence of the consciousness of Life as harmonious. With this change in the mental realm there takes place a change in the phenomenon which we usually speak of as the body.