3717. 'And I did not know it' means being in obscurity. This becomes clear without explanation, for 'not knowing' or being ignorant of something means obscurity so far as things understood by the mind are concerned. Because 'not knowing' or being ignorant of something means obscurity, and because also 'awakening from sleep' means becoming enlightened, one may see what the internal sense is and what this is like. That is to say, one may see that the nature of the images belonging to the literal sense is such that they present themselves to a person's external sight or any of his other senses and are also perceived by him as those senses perceive them. But the nature of the images belonging to the internal sense is such that these present themselves to a person's internal sight or any of his other inner sensory powers. The things therefore that are contained in the literal sense and are perceived by a person on the level of the external senses, that is, on the level of worldly images or of ideas formed from these, are perceived by the angels on the level of the internal senses, that is, on that of things in heaven or of ideas formed from these. The difference between images in the literal sense and those in the internal is like that between the things that belong to the light of the world and those that belong to the light of heaven. Those belonging to the light of the world are devoid of life compared with those belonging to the light of heaven; for the light of heaven holds wisdom and intelligence from the Lord within it, 3636, 3643. Consequently when things belonging to the light of the world are removed or cast away those that belong to the light of heaven are left, celestial images replacing earthly ones and spiritual replacing natural. So, as stated above, not knowing or being ignorant comes to mean being in a state of obscurity where good and truth are concerned, and 'awakening from sleep' comes to mean becoming enlightened. And it is similar with all other images in the literal sense.