The Millennium

Revelation 20:4-5

I saw thrones on which were seated those who had been given authority to judge. And I saw the souls of those who had been beheaded because of their testimony about Jesus and because of the word of God. They had not worshiped the beast or its image and had not received its mark on their foreheads or their hands. They came to life and reigned with Christ a thousand years. 

Three Views on the Millenium

Check out this article by Crossway:
https://www.crossway.org/articles/what-is-the-millenium-revelation-20/