Therefore this darkness of the body has been placed between us and God, like the cloud of old between the Egyptians and the Hebrews; Exod. xiv. 20. and this is perhaps what is meant by “He made darkness His secret place,” Ps. xviii. 11. namely our dulness, through which few can see even a little.  But as to this point, let those discuss it whose business it is; and let them ascend as far as possible in the examination.  To us who are (as Jeremiah saith), “prisoners of the earth,” Lam. iii. 34. and covered with the denseness of carnal nature, this at all events is known, that as it is impossible for a man to step over his own shadow, however fast he may move (for the shadow will always move on as fast as it is being overtaken) or, as it is impossible for the eye to draw near to visible objects apart from the intervening air and light, or for a fish to glide about outside of the waters; so it is quite impracticable for those who are in the body to be conversant with objects of pure thought apart altogether from bodily objects.  For something in our own environment is ever creeping in, even when the mind has most fully detached itself from the visible, and collected itself, and is attempting to apply itself to those invisible things which are akin to itself.