^20:3 He threw him into the Abyss, and locked and sealed it over him, to keep him from deceiving the nations anymore until the thousand years were ended. After that, he must be set free for a short time.

He THREW him into the ABYSS, and LOCKED and SEALED IT over him,

Again, this confirms that the devil is finite. Something that is infinite or omnipresent cannot be contained or THROWN. In a way, the angel sent by God is rather rude, not only is the devil thrown into the ABYSS, but the angel SHUTS the ABYSS and SEALS it over the devil's head. All this is written to make it absolutely clear to the reader that the devil will not be able to affect anything on the earth for the next 1000 years.

Some commentaries try to explain where the ABYSS is. Some think it is at the bottom of the ocean. That may be, given the case we have already made in this study that water is the "container of spirits". Others think it may be at the center of the earth. But from a spiritual viewpoint, the ABYSS may be right under our feet (Romans 16:17-20). Be aware, though, from the Romans portion of scripture, that it is GOD or his designated angel, in this case, who crushes Satan under your feet.

to keep him from DECEIVING THE NATIONS anymore UNTIL the THOUSAND YEARS were ended.

This is not the end of the devil or Satan (see verse 10). He just is inhibited from DECEIVING the NATIONS, meaning the unbelieving peoples. Furthermore, there is no indication that SEALING UP the devil in any way removes the evil nature from mankind. Rather, the sinful nature of mankind is merely repressed. During the THOUSAND YEARS, there will be a lot of "good people" on this earth. At least that is how it will appear to others. How often do we hear today that a person is a "good person" implying that they probably will go to heaven and not to hell. Yet after the THOUSAND YEARS, the latent evil in the "good person" will have a chance to realign itself with the devil again (verses 7 - 10). The astute reader already knows that the ONLY WAY to avoid hell is to have one's name in the Book of Life (verse 15). And, incidentally, LIFE begins with Jesus Christ (John 14:1-6-11).

That there are NATIONS, implies that there will be political boundaries during the 1000 years. It will be a peaceful time but not a lala land or utopia environment. There probably will be work to do as the sin curse (Genesis 3:17-21) still remains upon the land until this earth is destroyed (Revelation 21:1).

AFTER that, he must be set FREE for a short time.

Here is one of the few times in the Revelation that the timing is not precise. It is just a 'short time'. As a finite created being, the devil is kept in the dark about how much time (Revelation 12:12) he will have to perform his deceptions again.