We acknowledge God’s forgiveness of sin in the destruction of sin and the spiritual understanding that casts out evil as unreal. But the belief in sin is punished so long as the belief lasts.
Third tenet of Christian Science, Science and Health with Key to the Scriptures, p. 497
The third tenet trumpets the grand possibility that each of us can be lifted out of sin and the suffering that attends it. It heralds the hope of what Mary Baker Eddy, the Leader of the Christian Science movement, referred to as “. . . the higher mission of the Christ-power to take away the sins of the world” (Science and Health, p. 150).
Modeled after the methods of the Master—as in Christ Jesus’ freeing of the adulterous woman (see John 8:1–11) and his raising up of the impotent man at the pool of Bethesda (see John 5:1–14)—the tenet exposes the falsity of the belief in sin, the detrimental effects of accepting this belief, and it acknowledges the spiritual understanding that there simply is no sin in God and His creation. Thus the error of sin is “forgiven” only as it is destroyed.