Revelation 6:10-11

6:10 They cried out with a loud voice, “How long, Sovereign Master, holy and true, before you judge those who live on the earth and avenge our blood?” 6:11 Each of them was given a long white robe and they were told to rest for a little longer, until the full number was reached of both their fellow servants and their brothers who were going to be killed just as they had been.