Marcos 13:27

Evidently Jesus will bring all the elect together. This implies the resurrection of Old Testament saints (Daniel 12:2) and Tribulation saints who have died (Revelation 6:9-11). Probably Christians, saints of the church age who have gone to heaven at the Rapture or death, will return with Him (1 Thessalonians 4:17). Saints living on the earth when Jesus returns will also assemble to Him (cf. Matthew 25). Jesus pictured all believers converging to Him at His second coming whether alive or dead, on earth or in heaven. He will become the universal center of attention, and then He will begin reigning. Unbelievers will not experience resurrection until the end of Jesus’ millennial reign (Revelation 20:7-15).