Jeremiah 4:27

For thus hath the LORD said, The whole land shall be desolate; yet will I not make a full end.

The whole land is to be made desolate, yet without being brought to a complete end. This desolation comes after the great day of God, the Lord's second coming, and the final upheavals of the earth. It is the condition of the earth during the thousand years.

Its cities will be broken down. Its fruitful places will be turned into a broken, wilderness-like desolation. The earth will be reduced at least partly to the confusion and darkness of its beginning. No people or birds will remain on it.

In that broken wilderness condition the earth will be Satan's place of confinement during the thousand years, where he will see the effects of his rebellion and the curse he caused. While the land is left desolate, the saints will be preserved through the final upheavals and then taken away to meet Christ.