Revelation 6:9

I saw under the altar... — Read, when He opened, and, instead of “were slain,” &c., had been slain because of the Word of God, and (because of) the testimony which they held. The seal indicates that the mission of the Christian Church can only be carried out in suffering. An altar is seen, and at its foot tokens of the martyrs who had laid down their lives upon it. The word “souls” is to be taken as the equivalent of “lives”; the vision tells that their lives had been sacrificed. The blood of the victims was in the temple service poured out at the foot of the altar. St. Paul makes use of the same imagery — “I am now ready to be poured out” (“offered” in English version). In union with Christ Christians are called upon to suffer with Him, even to carry on to its great end the work of Christ in the world, and so fill up that which is lacking of the sufferings of Christ (Colossians 1:24). The word “souls” has been made a resting-place for an argument respecting the intermediate state. There is no ground for this: it is quite beside the object of the seal, which simply exhibits the sufferings of Christ’s people as the necessary accompaniment of the progress of the gospel. These sufferings are because of the Word of God and the testimony which they held. It was because of the Word of God and the testimony that the sacred seer himself suffered (Revelation 1:9). The words here remind us that the same issue which St. John fought, the suffering ones of after ages would be fighting. Their witness and his was the God-man; to this testimony they clung. They were not ashamed of Christ, or of His words, and they suffered for their courage and fidelity.