Although the Marriage of the Lamb will be in heaven before Jesus Christ comes to earth for his second coming, the Marriage Supper of the Lamb mentioned immediately after the marriage will not be in heaven. It will be back on earth during the Millennial Kingdom.
These slides present a fivefold argument that this supper will be during the Millennial Kingdom based upon these points: the prophetic nature of the announcement in heaven, the given order of events in Revelation 19-20, Jesus’ statements about when He would again drink the fruit of the vine, the prominence of feasts in the Millennial Kingdom, and the prophetic symbolism of the wedding feast at Cana.
These slides briefly discuss how Jesus’ parable about the wedding dinner as stated cannot indicate that the gospel would be taken to Gentiles as it is usually so interpreted. The parable declares that feasting will be prominent in the kingdom of heaven. Even so men will be rebellious and bring upon themselves God’s judgment.
See slides Marriage Supper of the Lamb for arguments about why the feast will be on earth during the Millennial Kingdom.