It is not true that this circumstance multiplies without cause, it is that Job and his friends do not yet know the cause. Even if they knew the cause, like us reading this, they may not understand the cause still. The cause is for God to know and for us to trust His judgement.
What does Job mean by destroy? He has not been destroyed. If it has been appointed for all men to die, if naked we come into and leave this life, if the possessions of this world only rust and rot away, what has been destroyed but our false notions and expectations? Being temporarily emptied is not the same as being destroyed. God has spared Job's life and has His purposes for such. Why isn't that the focus?
Deep depression brings a sense of profound thought that may not actually be there. The patient's mind is busily thinking even as others are answering him, consuming itself in what it thinks is profound. He thinks that he is on the brink of something big if he can just follow it through. It is not that he doesn't appreciate the counsel of others, he just can't silence his thoughts enough to listen because of the intrigue of this sudden perceived depth of thought. The perception is addictive. Rarely is the pursuit he makes anything more than the depression tangling and coiling itself further.
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