The people that walked in darkness have seen a great light: they that dwell in the land of the shadow of death, upon them hath the light shined.—Isaiah 9: 2.
To walk is to be in action or motion, to progress, to revolve, to turn, to pass through, over, along or upon. It implies standing erect, for one must first stand in order to step; in other words, get on his feet, and be balanced. So, to be walking in darkness is very different from sitting or lying in darkness.
Eleven years ago, I was sitting down and lying down in as great darkness as ever came to a mortal; in the depths of despair, and only too glad if it were the shadow of death for myself and child. Although a member of the Presbyterian church, always at prayer-meeting, always ready to take my share of the work, striving to live as a Christian should, no light penetrated the darkness, and, as the clouds of depression, disappointment, sickness, suffering, and failure came darker and heavier, I felt that the promises were almost a mockery. The more I trusted my God, the more error raged; the harder I tried to serve him, the more I was mocked, until finally, almost alone in a large city, I felt that if much more came, I should seek refuge in Lake Michigan; in fact, even reason was tottering. When, to human sense, the end had almost come, I clung to the Bible with all my power. Then it was that the words "Christian Science" were first spoken to me.