Revelation 12:1-2 And there appeared a great wonder in heaven; a woman clothed with the sun, and the moon under her feet, and upon her head a crown of twelve stars: And she being with child cried, travailing in birth, and pained to be delivered. (KJV)
The word translated as "wonder" in the KJV is translated "sign" in other versions. In the Greek the word is "semeion" (say-mi'-on) and means sign.
E.W. Bullinger writes in "Commentary on Revelation" page 387: "Here for the first time in this book we have a "Sign". We are warned not to take this literally but to see it as a sign of something else. The Holy Spirit guides us as to what is literal and what is not. We may gather that, when we are not so cautioned, we are not to treat the things in this book as symbols, but as literal facts and events."
It is a great sign: A woman with the sun, moon, and 12 stars.
Joseph was given a dream in Genesis 37:9-10 And he dreamed yet another dream, and told it his brethren, and said, Behold, I have dreamed a dream more; and, behold, the sun and the moon and the eleven stars made obeisance to me. And he told it to his father, and to his brethren: and his father rebuked him, and said unto him, What is this dream that thou hast dreamed? Shall I and thy mother and thy brethren indeed come to bow down ourselves to thee to the earth? (KJV)
This woman symbolizes "Israel". The 12 stars symbolize the 12 tribes, the "sun" symbolizes "Jacob" and the "moon" symbolizes "Rachael".
The baby she gives birth to is "Y'shua".
G-d cursed the serpent in
Genesis 3:15 And I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel. (KJV)
The seed of the woman, Y'shua, will crush the head of the serpent.
Revelation 12:3-4 And there appeared another wonder in heaven; and behold a great red dragon, having seven heads and ten horns, and seven crowns upon his heads. And his tail drew the third part of the stars of heaven, and did cast them to the earth: and the dragon stood before the woman which was ready to be delivered, for to devour her child as soon as it was born. (KJV)
The 2nd sign - A red dragon with 7 heads and 10 horns and 7 crowns on his heads. This is Satan.
Here is what the various parts of his description represent:
Red He is dripping with the blood of the martyrs slain by his human workers.
Dragon Voracious, powerful, and vicious
7 heads and crowns 7 is the number of completeness and they represent complete world dominion just as the 4 headed leopard in Dan 7:6 represented 4 geographical sections of the Greek empire.
10 horns These horns represent the same thing as the 10 toes in the statue in Daniel 2 and the 10 horns on the 4th beast in Daniel 7. They represent the 10 kingdoms of the revived Roman Empire.
(If you haven't read chapters 2 and 7 in our commentary on Daniel, please take the time to do so. I explain this in great detail there)
His original fall from heaven is alluded to here. Apparently 1/3 of the angels (stars) followed him becoming demons. (See Isaiah 14:12-15)
Rev 12:4 "the dragon stood before the woman which was ready to be delivered, for to devour her child as soon as it was born." (KJV) refers to His attempt to kill Y'shua at His birth. (See Matt 2:1-20)