Charles H. Spurgeon on Psalms 139:12

Yea, of a surety, beyond all denial. The darkness hideth not from thee; it veils nothing, it is not the medium of concealment in any degree what ever. It hides from men, but not from God. But the night shineth as the day: it is but another form of day: it shines, revealing all; it "shineth as the day," —quite as clearly and distinctly manifesting all that is done. The darkness and the light are both alike to thee. This sentence seems to sum up all that went before, and most emphatically puts the negative upon the faintest idea of hiding under the cover of night. Men cling to this notion, because it is easier and less expensive to hide under darkness than to journey to remote places; and therefore the foolish thought is here beaten to pieces by statements which in their varied forms effectually batter it. Yet the ungodly are still duped by their grovelling notions of God, and enquire, "How doth God know?" They must fancy that he is as limited in his powers of observation as they are, and yet if they would but consider for a moment they would conclude that he who could not see in the dark could not be God, and he who is not present everywhere could not be the Almighty Creator. Assuredly God is in all places, at all times, and nothing can by any possibility be kept away from his all observing, all comprehending mind. The Great Spirit comprehends within himself all time and space, and yet he is infinitely greater than these, or aught else that he has made.