He causes all, both small and great, rich and poor, free and slave, to receive a mark on their right hand or on their foreheads, and that no one may buy or sell except one who has the mark or the name of the beast, or the number of his name. Here is wisdom. Let him who has understanding calculate the number of the beast, for it is the number of a man: His number is six hundred and sixty-six. (Rev. Rev. 13:16-18+)John states that the Beast has a number associated with his name and that he who has understanding may calculate the number of the beast which is the number of a man, the infamous 666.