The great red dragon signifies the Devil, Satan (12:3-4). At the beginning of the next chapter there is a beast rising out of the great sea, the Mediterranean (13:1-2). This is Antichrist. Actually he is the coming Caesar, the last Caesar of the revived Roman Empire.
On this earth God has a harvest. This harvest signifies all the saints of the New Testament living on earth near the time of the Lord's return (14:15). From among these living believers will come the firstfruit. These will be some overcomers living among the believers who ripen earlier and become the firstfruit.
Babylon the Great signifies the Roman Church. She is called the great prostitute (17:1, 5) because of her sinful relationships with the rulers of the earth for her profit.
The wife of the Lamb, the bride in Revelation 19:7, will be all the overcomers throughout the generations, including those in Old Testament times, that is, the dead and resurrected overcomers plus the living overcomers (the firstfruit). They will be His bride in the thousand years (20:4-6). That one day will be the wedding day. A thousand years to the Lord is one day (2 Pet. 3:8). The entire millennium will be a wedding day. On the wedding day the wife is a bride, but after that day she becomes a wife. After the millennium in eternity the bride is the wife. All the overcomers among God's redeemed people will be His bride.
Now we come to the last sign, the New Jerusalem The New Jerusalem is the aggregate of all the lampstands. At the beginning of this book there are seven lampstands, local lampstands in this age. At the end of this book there is an aggregate, a composite lampstand, not the local ones but the eternal one, the universal one. Revelation begins with the lampstands and ends with the lampstand. The lampstands are signs of the churches; the New Jerusalem is also a lampstand, the sign of God's dwelling place.