37. As for the statement that 'the lights will be for signs, and for set times, and for days, and for years', this contains more arcana than can be presented at this point, though no arcanum at all is visible in the sense of the letter. For now only this can be said: Change in spiritual and celestial things takes place both on general and on particular scales, and is comparable to changes that take place through the day and through the year. Changes through the day are from morning to midday, from then on to evening, and through the night to the morning. Changes in the year similar, from spring to summer, from then on to autumn, and through winter to spring. These bring changes in temperature and amount of daylight, and so in the fertility of the earth. Compared to such changes are the changes that take place in spiritual and celestial things. Life without changes and variations would lead to sameness, and so no life at all. Good and truth would not be recognized and identified, let alone perceived. In the Prophets such changes are called 'ordinances', as in Jeremiah,

[Thus] said Jehovah who gives the sun for light by day and the ordinances of the moon and of the stars for light by night, These ordinances will not depart from before Me. Jeremiah 31:35-36.

And in the same prophet,

Thus said Jehovah, If I have not established My covenant of day and night, the ordinances of heaven and earth . . . Jeremiah 33:25.

But these things will in the Lord's Divine mercy be dealt with at Genesis 8:12.

7957. 'Both you and the children of Israel' means together with their truth from God, and with truth that leads to good and truth which springs from good. This is clear from the representation of 'Moses' as the truth from God, dealt with just above in 7955; and from the representation of 'the children of Israel' as those belonging to the spiritual Church, dealt with often, thus those guided by truth that leads to good and by truth which springs from good. For the spiritual Church differs from the celestial Church in that it is brought to the good of charity by means of the truth of faith, which being so it considers truth to be the essential thing. Initial contact with that good for them is effected through truth, for truth teaches them what they ought to do; and when they do that truth it is called good. This good, once they have been brought in contact with it, becomes the standpoint from which they see truths, that show them further how to act. From this it is evident that whether you say those belonging to the spiritual Church or those guided by truth through Which good is done, and by truth seen from the standpoint of good, it amounts to the same thing.