Revelation 6:11

And white robes were given unto every one of them; white robes of glory; for the white robes of Christ's righteousness, and of a holy life, were by them put on before they were slain. That they should rest yet for a little season; that they should be satisfied, and acquiesce in God's dispensations. Until their fellow-servants also and their brethren, that should be killed as they were; for God had yet more faithful witnesses to be martyred, (though not in such flocks as before), who should die for the same faith and profession. Should be fulfilled; when the number of those his martyrs should be completed, he would avenge their blood upon their enemies.