Revelation 12:2

and she was with child; and she crieth out, travailing in birth, and in pain to be delivered.

And she was with child ... This verse is not merely incidental. The hatred and opposition from Satan to both the woman and her child already existed before the child was born. Therefore, the satanic hatred could not have been the result of the Christ (the child) at some later date winning a victory over Satan. This is important to understanding later verses in the chapter.

Travailing in birth ... This is a fitting metaphor for the long endurance, patience, and suffering of God's ancient people (the true spiritual seed of Abraham) who were a despised minority of the proud, secular Israel during the long period of waiting for the birth of the Messiah. At times, there must have been many, like Elijah, who felt that they were utterly alone, and like the prophets must have prayed for God to "take away" their lives (1 Kings 18:22; 19:4). This was a time of "waiting for the consolation of Israel" (Luke 2:25).

This dramatic verse brings us near the time of the fulfillment of Genesis 3:15, for the child about to be born was the Seed of Woman, the Incarnate Son of God, the Lord Jesus Christ.