Revelation 13:16-18

Revised Standard Version Catholic Edition

¹⁶ Also it causes all, both small and great, both rich and poor, both free and slave, to be marked on the right hand or the forehead, ¹⁷ so that no one can buy or sell unless he has the mark, that is, the name of the beast or the number of its name. ¹⁸ This calls for wisdom: let him who has understanding reckon the number of the beast, for it is a human number, its number is six hundred and sixty-six.^[a][b]