The Catechism in Questions & Answers

635. What do the words “Your kingdom come” mean?

The kingdom of God has come to mankind in Christ. With the plea “Your kingdom come” believers pray that the nature of Christ may become more and more perceptible in the congregation. Beyond that, however, this plea is also a prayer that the future kingdom of God may soon be revealed: this will begin with the return of Christ to take home His bridal congregation.