Alcuin of York — on Rev 8:8-9 (COMMENTARY ON REVELATION)

“And the second angel sounded the trumpet: and as it were a great mountain, burning with fire, was cast into the sea, and the third part of the sea became blood: and the third part of those creatures died in it, which had life, and the third part of the ships was destroyed. The Devil is called a great mountain, whether because he wanted to be like the one about which it is said, In the last days the mountain of the house of the Lord shall be prepared, [Is. 2:2] or because in the end he will exalt himself above all that is called, or worshipped as, God. [2 Thes. 2:4] He is called burning because he is tormented by his own evilness and envy, because, ejected from among the saints by the angel sounding the trumpet, that is by the Church preaching, he is cast into the sea, that is into the incredulous — not that he was not already in them before, but since he has been ejected from among the saints, he starts ruling over the incredulous all the more. It seems that by the third that was turned into blood is symbolized the kind of death by which the two other thirds die, so that in one third is denoted the death, and in two thirds the number of the dying. The water turned into blood is fleshly wisdom, which kills souls; whence the apostle: Being wise according to the flesh is death. [Variant of Rom. 8:6] This wisdom means both bad credulity and wrong work; for with regards to wrong doctrine it is said, The letter killeth, [2 Cor. 3:6] and with regards to wrong work, Deliver me from bloods. [Ps. 50:16]”