Theologians have often talked about the kingdom of God in three different ways. First, there is the regnum potentiae, the kingdom of power. This is the dominion of Jesus Christ over the universe, the providential and judicial administration of all things which Christ exercises by virtue of being the eternal Son of God. Second, we can speak of the regnum gratiae, the kingdom of grace. This refers to Christ’s reign over his saved people, the spiritual kingship which Christ exercises by virtue of being our Mediator and the head of the church. Finally, there is the regnum gloriae, the kingdom of glory. This is Christ’s dominion in the age to come. The kingdom of glory is the kingdom of grace made perfect and complete.
Now look at the phrase “kingdom of power” in the last line of the Catechism’s answer. We pray “that [Christ] would be pleased so to exercise the kingdom of his power in all the world, as may best conduce to these ends.” Notice the ecclesial logic. The “these ends” have to do with the proclamation of the gospel, the saving of the lost, and the edification of the saints. In other words, Christ rules over all things for the good of the church. The kingdom of power is subservient in purpose to the kingdom of grace (giving way to the kingdom of glory), not the other way around.
By Kevin DeYoung