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.

9216. 'In which he may sleep' means resting on them. This is clear from the meaning of 'sleeping' as resting, in this instance on the external and sensory level, meant by 'clothing', 9212; for it says that it is clothing 'in which he may sleep'. How the explanation that more internal things find rest on the sensory level should be understood must be stated. The sensory level is the last and lowest of a person's life, as has been shown above. What is lowest contains all the more internal levels and is general to them all; for they terminate in it and accordingly rest on it. It is like the skin, for example, which is the outermost covering of the body. The body and all things in it terminate in the skin, because it contains them and they accordingly rest on the skin. In a similar way it is like the peritoneum within the body. Because it contains the abdominal organs, these rest on it and are also linked to it all round. Or equally it is like the pleura's relationship to the organs in the chest.

[2] A similar situation exists with all the things that compose a person's actual life, with those for instance that are connected with his understanding and those that are connected with his will. These too follow one another in order from more internal things to relatively external ones. The relatively external ones are factual knowledge together with its delights, while the outermost things are those of the senses, which are in contact with the world through sight, hearing, taste, smell, and touch. The more internal things rest on them since they terminate in them. These are the matters that are meant in the spiritual sense by 'the covering' or 'the clothing in which he may sleep'. The reason why things on the level of the senses are meant by 'the clothing' or 'the covering' lies in correspondences; for as stated above in 9212, spirits and angels appear dressed in garments in keeping with their truths of faith. Those governed by truths springing from good appear in shining ones, as for instance those at the Lord's tomb did, Luke 24:4; Matthew 28:3, and also in ones of fine, white linen, as for instance those referred to in Revelation 19:14 did; and others appear in garments of various colours.

[3] Furthermore it should be realized that all things without exception proceed in successive stages from their first or inmost level to their terminations on the last and lowest and rest on them. Each thing at a prior or more internal stage in order has its own connection with terminations on the lowest level. Therefore if things on the lowest level are dispelled those on interior levels are also scattered. This also explains why there are three heavens. The inmost or third heaven flows into the middle or second heaven; the middle or second heaven flows into the first or lowest heaven, which in turn flows into and resides with mankind. Consequently the human race constitutes the lowest level of order; in it heaven terminates and on it heaven rests. This being so, the Lord in His Divine [Love and Care] always provides for the presence among the human race of a Church in which truth revealed by God exists; such truth on our planet is the Word. By means of this a continuous link exists between the human race and the heavens. This is why every detail of the Word has within it an internal sense which exists for heaven's benefit and whose nature is such that it joins angels' minds to those of people on earth in so firm a bond that they act as one. All this goes to show yet again the nature of a situation in which interior things rest on those at the lowest level.