Mrs. Eddy writes in Science and Health: "The twelfth chapter of the Apocalypse typifies the divine method of warfare in Science, and the glorious results of this warfare. The following chapters depict the fatal effects of trying to meet error with error." Science and Health, p. 568
When will we learn to use "the divine method of warfare" and avoid "the fatal effects of trying to meet error with error"? The basis of Christian Science practice is that there is but one power, not two, and that this one power is good. Furthermore, because good, God, is Mind, this infinite power is present as consciousness, not as material force. The understanding of this one power causes a belief in a second power to fall back into nothingness before the conscious presence and power of Love.
On the other hand, to wage war with evil as a reality, instead of simply as a claim to reality, would be to perpetuate it, since all there is to a second power is the belief in it. Naturally, the belief in two powers is fatal to the understanding of omnipotence. That which fights error as reality is itself erroneous. The only place where evil can even claim to exist is in a mind that is not God, in a suppositious realm outside infinite Love, the one Life.