John Calvin Commentary Hebrews 4:13

"And there is no creature that is not manifest in his sight: but all things are naked and laid open before the eyes of him with whom we have to do." — Hebrews 4:13 (ASV)

Neither is there any creature, etc. The conjunction here, I believe, is causal and can be rendered as for; for in order to confirm this truth, that whatever is hidden in man is discerned and judged by God’s word, he draws an argument from the nature of God Himself. There is no creature, he says, that is hidden from the eyes of God; therefore, there is nothing so deep in man’s soul that cannot be drawn out into light by that word which resembles its own author, for as it is God’s role to search the heart, so He performs this examination by His word.

Interpreters, without considering that God’s word is like a long staff by which He examines and searches what lies deep in our hearts, have strangely distorted the meaning of this passage; and yet they have not thereby resolved the difficulty. But all difficulty disappears when we take this view: that we ought to obey God’s word in sincerity and with heartfelt affection, because God, who knows our hearts, has assigned to His word the role of penetrating even into our inmost thoughts.

The ambiguous meaning of the last words has also led interpreters astray, as they have rendered them, “Of whom we speak;” but they ought, on the contrary, to be rendered, With whom we have to do. The meaning is that it is God who deals with us, or with whom we have dealings; and therefore, we ought not to trifle with Him as with a mortal man, but whenever His word is set before us, we ought to tremble, for nothing is hidden from Him.