Charles Ellicott Commentary Revelation 3:21

"He that overcometh, I will give to him to sit down with me in my throne, as I also overcame, and sat down with my Father in his throne." — Revelation 3:21 (ASV)

To him that overcometh...—He will share Christ’s throne as Christ shared His Father’s throne. Here are two thrones mentioned. My throne, says Christ: this is the condition of glorified saints who sit with Christ in His throne. “But My Father’s (i.e., God’s) throne is the power of divine majesty.” Here none may sit but God, and the God-man Jesus Christ.

The promise of sharing the throne is the climax of an ascending series of glorious promises, which carry the thought from the Garden of Eden (Revelation 2:7) through the wilderness (Revelation 2:17), the temple (Revelation 3:12), to the throne. The promise bears marked resemblance to the language of Saint Paul to the Ephesians (Ephesians 2:6). This crowning promise is made to the most unpleasing of the churches.

But it is well that in this way the despondency which often succeeds the sudden collapse of self-satisfied imaginations should be met by so bright a prospect. Though their religion has been proved an empty thing, there is a hope which may well drive away despair. “The highest place is within the reach of the lowest; the faintest spark of grace may be fanned into the mightiest flame of divine love.”