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.

2943. 'To all entering into the gate of his city, saying' means matters of doctrine through which one comes to faith. This is clear from the meaning of 'a gate' as a place of entry and so as that which, in the same way as a door, leads in, dealt with in 2145, 2152, 2356, 2385, and from the meaning of 'a city' as truth, which constitutes faith, dealt with in 402, 2268, 2449, 2451, 2712. In the Ancient Church a city was not like the city of later or of modern times. That is to say, a city did not consist of a collection or gathering together of individuals but of separate families living side by side. A family descended from the same forefather constituted a city. The city of Nahor, for example, to which Abraham's servant went to betroth Rebekah to Isaac, Genesis 24:10, consisted of the family of Nahor which was there. And Shalem, the city of Shechem, to which Jacob came after his departure from Paddan Aram, Genesis 33:18 and the whole of Chapter 34, consisted of the family of Hamor and Shechem which was there. And the same was so with all other cities in those times.

[2] And as it had come down to them from the most ancient people that nations and families represented heavenly communities, and so the things of love and charity, 685, 1159, therefore when a city is mentioned instead of a family, and a people instead of a nation, truth that constitutes faith is meant. It is also why in the genuine sense the city of God and the holy city mean faith in the Lord. And as 'a city' meant faith, 'the gate of the city' means matters of doctrine through which one comes to faith. The same was also meant in the Jewish representative Church by the judges and elders sitting in the gate of the city and giving judgement there, as is evident from historical sections of the Word, and also in Zechariah,

These are the things that you shall do: Speak the truth, everyone to his companion; judge in your gates the truth and the judgement of peace. Zechariah 8:16.

And in Amos,

Hate evil, and love good, and establish judgement in the gate. Amos 5:15.

'A gate' also means the place of entry into the rational mind, and the rational mind is compared to a city, see 2851.