We're never helpless in the face of adverse material evidence. There's always something we can do when confronted by disease, lack, failure, or enmity. We can change the evidence. Mrs. Eddy states in Science and Health: "Erroneous belief is destroyed by truth. Change the evidence, and that disappears which before seemed real to this false belief, and the human consciousness rises higher." Science and Health, p. 297.
How do we "change the evidence"? Not by doing something to matter; not by humanly manipulating circumstances or people. We change the evidence of error, the testimony of material sense, by discerning through spiritual sense the evidence of truth and demonstrating what we discern.
Clearly, this isn't a mental exercise in which we close our eyes to a distressing situation by contemplating abstract spiritual ideas. Christian Scientists don't merely "tune out" error by ignoring it and focusing thought on spiritual truths. As we realize the facts of spiritual being which contradict the false evidence of the senses, error is not only put out of thought, it is destroyed. The presence of health, abundance, and opportunity is demonstrated right where disease, lack, and limitation appeared to be.