The book of Revelation culminates with the parousia—the coming of Jesus in glory (Rev. 19:11ff.), when dead Christians are brought back to life to rule with him as kings for a thousand years (Rev. 20). John then adds the crucial qualification:
“The rest of the dead did not come to life until the thousand years were finished. This is the first resurrection” (Rev. 20:4–5).
The latter, therefore, is a resurrection of dead Christians only, in advance of the rest of the dead—not one general resurrection of all dead people at the same time. Not surprisingly, throughout his letters Paul describes the same resurrection pattern.
In 1 Corinthians 15, Paul gives an ordered sequence:
“Messiah the first fruits, then those who belong to Messiah at his coming” (1 Cor. 15:23).
Paul does not say that every dead person is raised at the future parousia; he specifically identifies “those who belong to Messiah.” He then continues beyond that resurrection event to Jesus’ reign, during which enemies are still being subjected, with death itself finally abolished before “the end” comes (1 Cor. 15:24–28). Later in the same chapter, Paul says that at the trumpet the Christian dead are raised and "clothed with immortality" (1 Cor. 15:51–54). Again, his subject is not a simultaneous resurrection of every dead person at the parousia, but the resurrection of those who belong to Messiah.
Even more striking is Paul’s language in Philippians 3:10–11, where he speaks of attaining the “advance resurrection,” or “out-resurrection from among the dead.” (See also 1 Cor. 15:24. Rotherham has “the earlier resurrection, which is from among the dead.”) The compound Greek word exanastasis intensifies the ordinary word for resurrection and can be understood as an “out-resurrection”—that is, a resurrection out from among dead people. The expression naturally pictures some of the dead being raised—Christians first—while the rest of the dead remain dead (cf. Rev. 20:5). Paul is therefore not merely expressing the hope that he will someday be resurrected; he longs to attain this special, exclusive, and therefore “first” resurrection from among dead people. This naturally fits the wider New Testament description of dead Christians being raised "from among the dead" (Luke 14:14; 20:35; 1 Cor. 6:14; 2 Cor. 4:14).
The same limited focus appears in 1 Thessalonians 4:13–17. Paul says that “the dead in Messiah will rise first” (1 Thess. 4:16), not that Jesus will raise all dead people at his parousia. Although in the immediate context, the word “first” contrasts the dead Christians with the Christians still alive; nevertheless, the only dead people Paul identifies as being raised at the parousia are “the dead in Messiah.” His concern is specifically with dead Christians, whom Jesus will raise at his parousia and unite with Christians who are still alive.
Taken together, Paul and John fit naturally together: Christians are raised first to rule with the Messiah, while “the rest of the dead did not come to life until the thousand years were finished.” This two-resurrection schema is difficult to reconcile with some who claim that every dead person—Christians and non-Christians alike—is resurrected simultaneously at the parousia.
Paul’s language consistently points to a resurrection specifically of dead Christians at the future parousia: Christ the first fruits, then “those who belong to Messiah” (1 Cor. 15:23); “the dead in Messiah” rising (1 Thess. 4:16); and Paul longing to attain that unique “out-resurrection from among the dead” (Phil. 3:11). Revelation 20:4–5 then gives the fuller chronological description of this same “first resurrection” event: the saints come to life and rule with Messiah, while “the rest of the dead” remain dead until the thousand years are finished.