Revelation 6 speaks of souls who have been killed for the word of God and who cry out to God from under the altar and ask for justice. But how is that possible, if the dead are not alive and there is no communication in death?
Revelation 6
9 And when he opened the fifth seal, I saw under the altar the souls of them that were slain for the word of God, and for the testimony which they held.
10 And they cried with a loud voice, and said, Until when, O holy and true Owner, judgest thou not, nor avenged our blood among them that dwell on the earth?
11 And a white robe was given to every one of them, and it was spoken to them that they should rest a little while longer, until the number of their fellowservants and their brethren should be completed, who should be killed as they also were.
seven seals
In Revelation John describes things that God showed him regarding the future in the day of the Lord and that he saw in spirit (Rev.1:10). We would call this a vision.
Revelation 6 is an account of how the Lamb (Christ Jesus) opens the seven seals of a scroll. This scroll is the title deed of the land of Israel (Jer.32:8-14). Only He is worthy to open the scroll. The second through the fourth seal is a description of the great tribulation that will come upon the Jewish people, in which many will perish (Rev.6:3-8).
martyrs
Through the call of the two witnesses (Revelation 11), many will come to faith during the great tribulation, some of whom will flee from the land (Matt.24:16; Rev.12:6). Another part will be oppressed in the land and many will be killed (Rev.13:13). These believers who are killed are the martyrs described in Revelation 6:9-11.
vision
In Revelation 6 there is a vision in which an altar is seen. Under an altar we normally find the blood of the victims. But here there is no literal altar, but in this vision a figurative altar is seen. No blood is seen under the altar, but souls. It is the souls of victims who cry out for justice, “in our blood”. Blood and soul are synonymous concepts in Scripture.
Leviticus 17 (NKJV)
11 For the soul of the flesh is in the blood, and I have given it to you on the altar to make an atonement for your souls, for the blood makes atonement through the soul.
We find a number of times in the Bible that blood can ‘speak’. This is of course not literal, but figurative.
Genesis 4
10 And He said, What have you done? The voice of your brother’s blood cries out to Me from the face of the earth.
Hebrews 12
24 (…) and to the blood of sprinkling, which speaks better things than Abel.
imagery
The blood of Abel, killed by his brother, did not literally call to Cain, nor does “the blood of sprinkling” speak literally. The blood of the sprinkling is a figure of speech and ‘speaks’ of something else: of the slain Lamb. It is metaphorical language. This is also the case in the image in Revelation 6. There in the vision the souls under the altar cry out for justice.