'Reproof' in the Bible

Art not Thou of old, O Jehovah, my God, my Holy One? We do not die, O Jehovah, For judgment Thou hast appointed it, And, O Rock, for reproof Thou hast founded it.

On my charge I stand, and I station myself on a bulwark, and I watch to see what He doth speak against me, and what I do reply to my reproof.