One of the events that occurs after the Second Coming of Christ has caused some question in the minds of believers. After Christ returns, He has Satan bound for a thousand years. However at the end of the thousand years, He releases Satan for a short period of time.
And when the thousand years are finished, Satan shall be loosed out of his prison, and shall come forth to deceive the nations which are in the four corners of the earth, Gog and Magog, to gather them together to the war: the number of whom is as the sand of the sea. And they went up over the breadth of the earth, and compassed the camp of the saints about, and the beloved city: and fire came down out of heaven, and devoured them (Revelation 20:7-9).
Why would God do something like this? Once Christ has returned and Satan has been bound, why allow him to be released for a short time and deceive the nations?
Is Already Bound
First, there are some who believe that Satan has already been bound. They argue that his release will be soon before Christ comes again, and not after the Millennium - the thousand year reign of Christ.
Has Not Been Bound
Other believers see the binding of Satan as something future. If this is the case, then the Bible gives us no reasons as to why this happens. There have been several different answers that have been offered to this question.
No Excuse For Anyone
Many see the release of Satan as one last chance to show humanity that they have no real excuse for rejecting the truth of God. The excuse that is often used is as follows: if people only knew that God existed, then they would believe in Him. During this last rebellion of Satan, there will be no one denying God's existence. Even though people know that God exists, and that He is a loving and caring God, some will still refuse to follow Him. By allowing this scenario, God will once-and-for-all show humanity that rejecting Him is not based upon the fact that we cannot see Him. Even when people know that God exists, they will still reject Him.
Sin In The Heart
This shows that sin remains in the human heart apart from any influence of the Devil. Not now, and not in the future, can all evil be blamed upon Satan and his evil forces. Sin is found in the human heart. The Bible says.
The heart is devious above all else; it is perverse - who can understand it? (Jeremiah 17:9).
Summary
After Christ returns, Satan will be released for a short time to deceive the nations. As to why, we are not told. Some Christians see this release before the coming of Christ rather than after He returns.