Revelation 6:11 in the World English Bible
A long white robe was given to each of them. They were told that they should rest yet for a while, until their fellow servants and their brothers, who would also be killed even as they were, should complete their course.
Context
10 And they cried with a loud voice, saying, How long, O Lord, holy and true, dost thou not judge and avenge our blood on them that dwell on the earth?
11 And white robes were given unto every one of them; and it was said unto them, that they should rest yet for a little season, until their fellowservants also and their brethren, that should be killed as they were, should be fulfilled.
12 And I beheld when he had opened the sixth seal, and, lo, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became as blood;