The terrors of the deep

I just had to include an excerpt from Moby Dick.  At this point in the book (Penguin Classics p. 453) one of the young negro boys named Pip is sent out onto one of the boats as an oarsmen to chase after a whale.  While on the boat, he is tossed overboard and is forced to keep himself afloat on the vast ocean for some time while all the other boats are off in the distance.  Being alone in infinite space has a special affect on the boy:

"... Pip's ringed horizon began to expand around him miserably.  By the merest chance the ship itself at last rescued him; but from that hour the little negro went about the deck an idiot; such, at least, they said he was.  The sea had jeeringly kept his finite body up, but drowned the infinite of his soul.  Not drowned entirely, though.  Rather carried down alive to wondrous depths, where strange shapes of the unwarped primal world glided to and fro before his passive eyes; and the misermerman, Wisdom, revealed his hoarded heaps; and among the joyous, heartless, ever-juvenile eternities, Pip saw the multitudinous, God-omnipresent, coral insects, that out of the firmament of waters heaved the colossal orbs.  He saw God's foot upon the treadle of the loom, and spoke it; and therefore his shipmates called him mad.  So man's insanity is heaven's sense; and wandering from all mortal reason, man comes at last to that celestial thought, which to reason, is absurd and frantic; and weal or woe, feeds theirs uncompromised, indifferent as his God.

I'm having trouble dissecting the final sentence.  It appears that Melville is saying that sensing the incomprehensible workings of the other world is akin to madness.  That the rational mind knows to leave well enough alone and simply keeps a steady course away from those corners - indifferent to them as God is indiferrent to us.  It's a powerful statement not only of abandonment on the one hand, but faith in the other.  The ship does come to rescue Pip, and although there may be indifference, God still keeps his "... foot upon the treadle of the loom.