3. Biblical evidence for the intermediate state.
On our understanding, the “first resurrection” describes an intermediate, beginning eternal state between physical death and physical resurrection. Some contend that there is no example in the Bible of the eternal state being a state of resurrection existence, but that is not the case. In Rev. 2:10-11, believers are promised that if they remain faithful until physical death, they will receive the crown of life,” which in turn will prevent them from being harmed by the second, spiritual death.
It could reasonably be assumed that the “life” referred to here is the heavenly existence of the saints between physical death and physical resurrection and is consummated in physical resurrection. The same truth is presented in 6:9-11, where deceased saints appear as living souls without bodies, waiting for the physical resurrection. Jesus taught the same when He said to the Sadducees that God “is not the God of the dead, but of the living; for all live to Him” (Luke 20:38). Therefore, said Jesus, God is still the God of Abraham, Isaac and Jacob, who are “sons of the resurrection” (Luke 20:36) and thus presently alive to Him, even before their final physical resurrection. The Sadducees denied not only the physical resurrection but also that there was any conscious existence after death, and in this passage Jesus rejects both false beliefs. The metaphorical picture is that of a soul leaving an earthly body and ascending to heaven, where a more intense condition of blessedness is experienced.
This is similar to Phil. 1:21, 23: “to die is gain…to depart and be with Christ is very much better” (cf. also 2 Cor. 5:8: “we…prefer rather to be absent from the body and at home with the Lord”). Paul states in Rom. 6:4-5 that our life in Christ can be referred to as a spiritual resurrection, and that life in Christ continues on into the intermediate state, after physical death. 1 Pet. 4:6 refers to people who, “though they are judged in the flesh as men” [= physical death], “may live [zaō = living in the intermediate state] in the Spirit according to the will of God.”
In the light of this and other Scriptures, it is reasonable to interpret the ascent of the soul at the time of death into the Lord’s presence as a form of spiritual resurrection, in anticipation of the physical resurrection and consummation of eternal life, which will occur at the Lord’s return. That such a translation can be termed a “resurrection” is appropriate, because the souls of the saints are entering a higher state of blessedness and resurrection existence than they had before on account of their regeneration (for a similar thought in early Christian literature, see Ignatius, Romans 2.2; 4.3; 1 Clement 5.4, 7; Acts of Paul), and because they experience the immediate presence of God and Christ (Rev. 6:9-11; 7:14-17). Consequently their role as kings and priests becomes intensifed. Their labor of perseverance on earth is successfully accomplished so that they can rest (6:11; 14:13). They have greater assurance of vindication (see on 6:11; cf. 19:8) and of protection from the second death, because of their intermediate existence of escalated spiritual life.
-G. K. Beale with David Campbell, Revelation: A Shorter Commentary, 442-443.