Vivi missi sunt hi duo in stagnum ignis ardentis sulphure … Nullus enim mortalium durius peccat haereticis, qui Christum postquam cognoverint, negant.”

– Beda Venerabilis, Explanatio Apocalypsis, Liber III

These two were thrown alive into the pool of fire burning with sulphur …. No mortal sins more greviously than do the heretics who deny Christ after they have known Him.”

Bede the Venerable, Commentary on Revelation, Book 3