What Does it Mean to Sit with Christ on His Throne

To him that overcometh will I grant to sit with me in my throne . . . (Revelation 3:21)

Question: What is the literal meaning, or inference, of Revelation 3:21 where Jesus told the twelve apostles, they would sit on twelve thrones judging the twelve tribes of Israel? Is it only a reference to the role of judgment over the Jews and the nations? Or, is