664. And after three days and a half.- That this signifies when completed, thus the end of the old church, and the beginning of a new church, is evident from the signification of three days and a half, as denoting fulness or completion at the end of the old church, when there is the beginning of a new church, concerning which see above (n. 658). The reason why it is said, after three days and a half, is, that days, in the Word, signify states, here, the last state of the church. For all times, in the Word, as hours, days, weeks, months, years, and ages, signify states in the Word, as in this case, the last state of the church, when there is no longer any good of love or truth of faith remaining. Because days signify states, and since in the first chapter of Genesis the establishment of the Most Ancient Church is treated of which was accomplished successively from one state to another, therefore it is said there that there was evening and there was morning the first, the second, the third, the fourth, the fifth, and sixth days, unto the seventh, when it was completed (Genesis 1:5, 8, 13, 19, 23, 31), and the days there do not mean days, but the successive states of the regeneration of men at that time, and the consequent establishment of the church with them. So also elsewhere in the Word.

In the Word, “light” in the highest sense represents Divine Truth: knowledge, ideas, understanding that come to us from the Lord. In lesser degrees -- the light of a lamp, the light of the moon and so forth -- it represents lower levels of truth, ideas and understanding drawn from more earthly sources. Also, the sun in the Word represents the Lord, with its heat representing the divine love and its light representing the divine wisdom. That wisdom flows into our minds and enters our lives in the form of truth -- things we can know and ponder that lead us and help us to be good people. This connection between light and thought is one of many spiritual/natural relationships that's embedded in our common language. People “see the light” when they understand something; we try to “shed some light” by bringing new thoughts to a difficult question; people are “enlightened” when they get new information or a more complete understanding of something. And a light bulb in a cartoon represents an idea!