To fear God and to obey the voice of the Servant would seem to imply having an abundance of light. But on reflection, that is not necessarily the case. Those who follow this Servant may indeed walk with him into the darkness of frustration, injustice, humiliation, and abuse. But this does not mean they should forgo their reliance on God. Through all the ages the children of God have equated God’s blessing with comfort and a sense of well-being. But that was not the way of the Servant. So the challenge is again and again: do not cast away your confidence. Wait on the Lord. Put your hope in him. Trust in the reputation and the character (the name) of the Lord, and rely on your God.
John N. Oswalt, The Book of Isaiah, Chapters 40–66, The New International Commentary on the Old Testament (Grand Rapids, MI: Wm. B. Eerdmans Publishing Co., 1998), 329.