935. That “summer and winter” signify the state of the regenerate man as to his new will, the alternations of which are as summer and winter, is evident from what has been said about cold and heat. The alternations with those who are to be regenerated are likened to cold and heat, but the alternations with those who have been regenerated are likened to summer and winter. That in the former case the man who is to be regenerated is treated of, and in the present case the man who has been regenerated, is evident from this, that in the one case cold is named first, and heat second; whereas in the other case summer is first named, and winter second. The reason is that a man who is being regenerated begins from cold, that is, from no faith and charity; but when he has been regenerated, he begins from charity.

[2] That there are alternations with the regenerate man—now no charity, and now some charity—is clearly evident for the reason that in everyone, even when regenerated, there is nothing but evil, and everything good is the Lord’s alone. And since there is nothing but evil in him, he cannot but undergo alternations and now be as it were in summer, that is, in charity, and now in winter, that is, in no charity. Such alternations exist in order that man may be perfected more and more, and thus be rendered more and more happy, and they take place with the regenerate man not only while he lives in the body, but also when he comes into the other life, for without alternations as of summer and winter as to what is of his will, and as of day and night as to what is of his understanding, he cannot possibly be perfected and rendered more happy; but in the other life these alternations are like those of summer and winter in the temperate zones, and those of day and night in springtime.

[3] These states are also described in the Prophets by “summer and winter” and by “day and night;” as in Zechariah:

And it shall come to pass in that day that living waters shall go out from Jerusalem; half of them toward the eastern sea, and half of them toward the western sea; in summer and in winter shall it be (Zechariah 14:8),where the New Jerusalem is treated of, or the kingdom of the Lord in heaven and on earth, that is, its state of both kinds, which is called “summer and winter.”

In David:

The day is Thine, the night also is Thine; Thou hast prepared the light and the sun, Thou hast set all the borders of the earth, Thou hast made summer and winter (Psalms 74:16-17), where like things are involved.

So in Jeremiah:

That the covenant of the day, and the covenant of the night be not made vain, that there may be day and night in their season (Jeremiah 33:20).