The Holy Bible, Revelation 20:1-3,7-10

1 And I saw an angel come down from heaven, having the key of the bottomless pit and a great chain in his hand.

2 And he laid hold on the dragon, that old serpent, which is the Devil, and Satan, and bound him a thousand years,

3 And cast him into the bottomless pit, and shut him up, and set a seal upon him, that he should deceive the nations no more, till the thousand years should be fulfilled: and after that he must be loosed a little season.

7 And when the thousand years are expired, Satan shall be loosed out of his prison,

8 And shall go out to deceive the nations which are in the four quarters of the earth, Gog and Magog, to gather them together to battle: the number of whom is as the sand of the sea.

9 And they went up on the breadth of the earth, and compassed the camp of the saints about, and the beloved city: and fire came down from God out of heaven, and devoured them.

10 And the devil that deceived them was cast into the lake of fire and brimstone, where the beast and the false prophet are, and shall be tormented day and night for ever and ever.

The Doctrine and Covenants, Section 29:22

22 And again, verily, verily, I say unto you that when the thousand years are ended, and men again begin to deny their God, then will I spare the earth but for a little season;

The Doctrine and Covenants, Section 43:30-31

30 For the great Millennium, of which I have spoken by the mouth of my servants, shall come.

31 For Satan shall be bound, and when he is loosed again he shall only reign for a little season, and then cometh the end of the earth.

The Doctrine and Covenants, Section 88:110-111

110 And so on, until the seventh angel shall sound his trump; and he shall stand forth upon the land and upon the sea, and swear in the name of him who sitteth upon the throne, that there shall be time no longer; and Satan shall be bound, that old serpent, who is called the devil, and shall not be loosed for the space of a thousand years.

111 And then he shall be loosed for a little season, that he may gather together his armies.

Journal of Discourses, George Q. Cannon 16:16

When we carry out the purposes and the revelations which God has given and made known unto us, we gain immensely. We gain power and strength, and in a little while the adversary will be bound in our midst, so that he will not have power to tempt us, and this will be brought about by our obeying the commandments of God and the revelations of the Lord Jesus Christ. I also believe that when Satan is loosed again for a little while, when the thousand years shall be ended, it will be through mankind departing from the practice of those principles which God has revealed, and this Order of Enoch probably among the rest. He can, in no better way, obtain power over the hearts of the children of men, than by appealing to their cupidity, avarice, and low, selfish desires. This is a fruitful cause of difficulty. You can handle men better in any other way than when you come to their money, and all these temporal things they are surrounded with. I hope to see a change in this respect, I pray for it, I am willing to labor for it. I hope you will give this subject your attention, and seek by all the faith in your power to prepare yourselves for it, and to prepare your children for it, so that when it is deemed wisdom by the servants of God to enter upon this system, we shall be prepared.