The prayer of these "souls" is like an accusing question (How long . . . until you judge the inhabitants of the earth and avenge our blood?), tempered by a reverent address to God as Sovereign Lord, holy and true. It is a prayer for justice or vindication that borders on vengeance and echoes such biblical prayers as Psalm 79:5-7 ("How long, O LORD? Will you be angry forever? How long will your jealousy burn like fire? Pour out your wrath on the nations that do not acknowledge you, on the kingdoms that do not call on your name; for they have devoured Jacob and destroyed his homeland") or 79:10 ("Why should the nations say, `Where is their God?' Before our eyes, make known among the nations that you avenge the outpoured blood of your servants").
This anguished plea for justice is sometimes compared unfavorably with the prayer of Jesus on the cross (Lk 23:34) or the prayer of Stephen at his martyrdom (Acts 7:60), both for the forgiveness of their tormentors. Kiddle (1940:119) states that "the modern conscience is shocked at the passionate longing for vengeance breathed out by the martyrs, and, indeed, it is beyond doubt lower in tone than the lofty spirit of forbearance which distinguished the Christian church in its earliest days." R. H. Charles (1920:1.176) places the prayer in a long tradition of apocalyptic Jewish prayers of vindictive martyrs, with the cautionary note that the offending call for vengeance is "made here once and for all and not uninterruptedly pressed as in Judaism."
Such comments, aside from their not-so-subtle anti-Semitism (as if Judaism taught vengeance while Christianity always urged unlimited forgiveness), presuppose a rather one-sided understanding of the ethics of both Jesus and Paul. Jesus asked in connection with one of his parables, "And will not God bring about justice [literally "retribution"] for his chosen ones, who cry out to him day and night?" (Lk 18:7). When he blessed "those who hunger and thirst for righteousness" (Mt 5:6), his words could as easily be translated, "those who hunger and thirst for justice." As for Paul, he urged kindness toward our enemy in order to "heap burning coals on his head" (Rom 12:20). If liberation theology has taught us nothing else, it has taught us that God's love and forgiveness can never be divorced from God's justice, or judgment on evil. The words of the ancient prophet, "let justice roll on like a river, righteousness like a never-failing stream" (Amos 5:24), are nowhere countermanded in the New Testament. The prayer of the martyrs in Revelation is not a cry for personal vengeance, but an appeal to a "Sovereign Lord, holy and true" to bring about justice in the world by destroying the powers of evil. It is an eschatological prayer, no different in its import from "your kingdom come" (Mt 6:10), "deliver us from the evil one" (Mt 6:13), "come, O Lord" (Aramaic marana tha) with its accompanying curse on anyone who "does not love the Lord" (1 Cor 16:22) or even "come, Lord Jesus" at the end of Revelation itself (22:20), just after a pair of solemn warnings to those who add to or take away from what is written.
In the context of the opening of the seals, the martyrs' prayer is simply a prayer for the series to continue to its appointed end. It has the same function as the four living creatures' repeated summons to the four horsemen to "Come!" (vv. 1, 3, 5, 7). The series will indeed continue, but the immediate answer to the prayer is a kind of stopgap measure. Each of the martyrs is given a white robe and is told to wait a little longer, until the number of their fellow servants and brothers who were to be killed as they had been was completed (v. 11). Their number will be complete when the sixth seal is opened, and the white robes will enable John--and us--to recognize these martyrs when we see them again (7:9, 13-14).