Revelation 6:9; Revelation 6:10

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;

10 and they cried out with a loud voice, saying, "How long , O Lord , holy and true, will You refrain from judging and avenging our blood on those who dwell on the earth?"