When the fifth seal was broken/opened by the Lamb, John saw underneath the altar the souls of them that had been slain for the word of God, and for the testimony which they held. These dead saints are men and women who lived and died before the incarnation and earthly work of the Christ. These Old Testament worthies would not be perfected or redeemed apart from those who would go through the great tribulation (Rev. 7:14, cf. Hebrews 11:40). According to Jesus, the judgement of the dead would include people who lived all the way back to creation (Matt. 23:31-36) and consist of all nations (Matt. 25:31-46; 12:41-42). Since the ending of this heavens and earth period would also begin the millennial reign of Christ with His saints, this judgment of the dead of which the souls under the altar included, we could rightly refer to it as a premillennial judgment of the dead that was to “shortly come to pass (Rev. 1:1).
These souls under the altar cry to be avenged by saying,”How long do you not judge and avenge our blood on them that dwell on the earth? They are dead but anticipate God to avenge their blood on people who are alive on earth. Abel has waited a long time (Matthew 23:35; Heb. 11:4; 12:24) as have a host of others (Hebrews 11:5-39). At last, Cain is about to receive the judgment that was due and be banished from the presence of God to a place prepared for the Devil and his angels (Matt. 25:41; Rev. 19:20; 20:10). Vengeance belongs to God (Rom. 12:19-21) and yet, they seek vindication and justice to be executed. In addition, when God executes His wrath and vengeance on the ungodly, it becomes a time of celebration (Rev. 16:7; 18:20; 19:1,2).
God does not correct their impatience. Injustice stirs the hearts of the godly and we may want to stop the wrongs committed against the saints as Jesus is seen standing on His feet when Stephen was being stoned to death. No one knew the appointed time that God would unleash his power in judgment. Even Jesus, while on earth, did not know the day or the hour (Matthew 24:36). Instead of reprimanding them, each one of these souls was given a white robe and told to rest for a little time, until their fellow servants and brethren, who would be killed, have fulfilled their course (v. 11). It is important to note the phrase, “little time” and appears to be connected to that generation (seventy to eighty years, Psalm 90:10). They did not have to wait that long as that generation was well into half-finished when this book was written. Notice the mention of judgment on that generation in the following texts of Scripture: Matthew 12:41-42, 45; 23:36; 24:34; Luke 11:50-51, 17:25; Acts 2:40.
It appears to this writer that we have two groups who are blessed in the first resurrection (Rev. 20:5-6). First, the Old Testament faithful and their New Testament faithful who had yet to fulfill their course, such as Paul (2 Tim. 4:7). These two are the 144,000 whom God has sealed out of every tribe of Israel (Rev. 7:4), first-fruits unto God and the Lamb (Rev. 14:4), and who would be blessed in the first resurrection (Rev. 20:5-6).