When do the Old Testament saints rise, and what role do they have at the marriage supper?
The Old Testament saints rise sometime after the kingdom has begun, as Daniel was told. At the marriage supper of the Lamb, they serve as the wedding guests, distinct from the church-age believers who form the main harvest. They belong to Daniel's company within the first resurrection of believers.
Les explains that the first resurrection of believers includes several categories: the firstfruits, those who arose from the graves on resurrection morning; Christ Himself, the firstfruit; the main harvest, the church-age believer; and then the Old Testament saints, Daniel's company. Those Old Testament saints come up on the scene sometime after the kingdom has begun. At the marriage supper of the Lamb, they are more or less the wedding guests. The lost are not resurrected until after the kingdom has ended, and tribulation saints are in a separate resurrection or translation.