The Catechism in Questions & Answers

409. What can be said of the future of the church of Jesus Christ?

At the return of Christ, one part of the church—the bridal congregation—will be caught up to God. Another part of the church will remain on earth and must prove itself in antichristian tribulations. In the kingdom of peace the church will be revealed when the royal priesthood proclaims the gospel to all human beings who have ever lived. In the new creation, worship and praise will be brought to God forever.

Kingdom of peace: see Questions 575. et seq. Royal priesthood: see Question 574., 577. New creation: see Question 581.