Opening of the fifth seal at the Apocalypse. "When he opened the fifth seal, I saw under the altar the souls of those who had been slain because of the word of God and the testimony they had maintained. They called out in a loud voice, 'How long, Sovereign Lord, holy and true, until you judge the inhabitants of the earth and avenge our blood?' Then each of them was given a white robe, and they were told to wait a little longer" (Rev. 6:9-11). Fresco in the Crypt of St. Magnus (1237), Cattedrale di Santa Maria, Anagni, Lazio, Italy.