In a trial, you may be deliberately left without light. There, you become a negative to be developed into a picture of light for that situation. Not for its benefits, but for God's glory. Situations are not used to prove God's ability, but to produce God's power to glorify Him in their midst.
In this large room of darkness, God does not even allow you to fellowship your way out. You may not have peace in it. There may not be any feelings of security or any evidence that God is even in it. Its purpose? That your mind would stay itself upon God. You are not there to prove God, but you trust Him without any proof. You don't require answered prayer, because you believe God even when prayers seem unanswered. You don't require God to bless you to experience His blessing. You experience His blessing on the basis of not being blessed because you are satisfied with Him alone, not with anything that He does. You are ready for the furnace, for the jail at midnight, for the rejection, because your mind is stayed. You do not feel love and, yet, you are not troubled. God is not revealing anything and there is no answer. You are not operating in life that you have experienced, but you are operating in a measure of God's life that you have never experienced.
If you are being used as God's man or woman, you have either been there or you are going there or you are there now, walking in darkness with no light.