Revelation 6:9

6 And I heard as it were a voice in the midst of the four living creatures saying, A measure of wheat for a shilling, and three measures of barley for a shilling; and the oil and the wine hurt thou not.

7 And when he opened the fourth seal, I heard the voice of the fourth living creature saying, Come.

8 And I saw, and behold, a pale horse: and he that sat upon him, his name was Death; and Hades followed with him. And there was given unto them authority over the fourth part of the earth, to kill with sword, and with famine, and with death, and by the wild beasts of the earth.

9 And when he opened the fifth seal, I saw underneath the altar the souls of them that had been slain for the word of God, and for the testimony which they held:

10 and they cried with a great voice, saying, How long, O Master, the holy and true, dost thou not judge and avenge our blood on them that dwell on the earth?

11 And there was given them to each one a white robe; and it was said unto them, that they should rest yet for a little time, until their fellow-servants also and their brethren, who should be killed even as they were, should have fulfilled [their course].

12 And I saw when he opened the sixth seal, and there was a great earthquake; and the sun became black as sackcloth of hair, and the whole moon became as blood;