The Catechism in Questions & Answers

567. What will transpire at the “marriage of the Lamb”?

The bridal congregation will be permitted to share in Christ’s glory and will be in direct and indissoluble fellowship with God.

Bridal congregation: see Questions 562. et seq.

“Alleluia! For the Lord God Omnipotent reigns! Let us be glad and rejoice and give Him glory, for the marriage of the Lamb has come, and His wife has made herself ready.” And to her it was granted to be arrayed in fine linen, clean and bright, for the fine linen is the righteous acts of the saints. Then he said to me, ‘Write: “Blessed are those who are called to the marriage supper of the Lamb”’.”
Revelation 19: 6-9