Seven, as in Revelation 15:1, signifies everything in an universal sense. The number 'seven' was considered holy, as is well known, because of the six days of creation, and the seventh, which is the celestial self, where peace, rest, and the Sabbath is. The number seven occurs so frequently in the rites of the Jewish church and is held holy everywhere.

So times were divided into seven, longer and shorter intervals, and were called weeks, like the great intervals of times till the coming of the Messiah, in Daniel 9:24-25. The time of seven years is called 'a week' by Laban and Jacob, as in Genesis 29:27-28. So wherever the number seven occurs, it is considered holy and sacred, as in Psalm 119:164, and in Isaiah 30:26.

As the periods of a person's regeneration are distinguished into six, prior to the seventh, or the celestial self, so the times of vastation are also distinguished, until nothing celestial is left. This was represented by the many captivities of the Jews, and by the last Babylonian captivity, which lasted seven decades, or seventy years. This was also represented by Nebuchadnezzar, in Daniel 4:16, 22, 29. It also refers to the vastation of the end times, in Revelation 15:1, 7-8. They should 'tread the holy city under foot, forty and two months, or six times seven,' as in Revelation 11:2 and Revelation 5:1. So the severity and increments of punishment were expressed by the number seven, as in Leviticus 26:18, 21, 24, 28 and Psalm 79:12.

(Odkazy: Apocalypse Explained 5, 7-8, 15; Arcana Coelestia 395; Daniel 9, 9:24, 9:25; Psalms 119)

3223. There are two forms of light that give light to man, the light of the world and the light of heaven. The light of the world comes from the sun, the light of heaven from the Lord. The light of the world is intended for the natural or external man, and so for things that exist within the natural man. Although these things do not appear to belong to that light, nevertheless they do, for the natural man is not able to grasp anything except by means of such things as occur and are visible in the world of the natural sun, thus unless they are given some visible form by the light and the shade of that world. All concepts of time and concepts of space, which in the natural man play so great a role that without them he is incapable of thought, belong also to the light of the world. The light of heaven however is intended for the spiritual or internal man. Man's interior mind, where his intellectual concepts reside that are called immaterial, belongs in that light. Of this no one is immediately conscious even though he refers to his intellect as sight and attributes light to it. The reason why he is not immediately conscious of it is that as long as he is engrossed in worldly and bodily interests his perception is solely of such things as belong to the light of the world and not of such as belong to the light of heaven. The light of heaven comes from the Lord alone, and the whole of heaven is bathed in that light.

[2] This light - the light of heaven - is immeasurably more perfect than the light of the world. Things which in the light of the world make a single ray make myriads in the light of heaven. The light of heaven holds intelligence and wisdom within it. This is the light which flows into the light of the world which shines in the external or natural man and causes the latter to perceive things with the senses. Unless the light of heaven were flowing in a person would have no discernment at all, for the life present in things which belong to the light of the world is received from that inflowing light. Between these two forms of light - that is, between things that belong to the light of heaven and those that belong to the light of the world - a correspondence exists when the external or natural man makes one with the internal or spiritual man, that is, when the external man is subservient to the internal. In this case things that occur in the light of the world are representative of such as occur in the light of heaven.