Revelation 6:9; Revelation 6:11

9 When the Lamb broke the fifth seal, I saw underneath the altar the souls of those who had been slain because of the word of God, and because of the testimony which they had maintained;

11 And there was given to each of them a white robe; and they were told that they should rest for a little while longer, until the number of their fellow servants and their brethren who were to be killed even as they had been, would be completed also.