Apocalypse Revealed #536
536. And another sign appeared in heaven. (12:3) This symbolizes a revelation from the Lord concerning people antagonistic to the New Church and its doctrine.
A sign symbolizes a revelation from the Lord, as in no. 532 above. It is called another sign because it is a revelation concerning people who will be antagonistic to the New Church.
Isaiah 13:6-8
6
Wail; for the day of Yahweh is at hand! It will come as destruction from the Almighty.
7
Therefore all hands will be feeble, and everyone's heart will melt.
8
They will be dismayed. Pangs and sorrows will seize them. They will be in pain like a woman in labor. They will look in amazement one at another. Their faces will be faces of flame.