Revelation 12:1-3

And a great sign [warning of an ominous and frightening future event] appeared in heaven: a woman clothed with the sun, with the moon beneath her feet, and on her head a crown of twelve stars. She was with child (the Messiah) and she cried out, being in labor and in pain to give birth. [Rom 9:4, 5] Then another sign [of warning] was seen in heaven: behold, a great fiery red dragon (Satan) with seven heads and ten horns, and on his heads were seven royal crowns (diadems). [Dan 7:7]