Revelation 13:16-18

Christian Standard Bible

¹⁶ And it makes everyone—small and great, rich and poor, free and slave—to receive a mark on his right hand or on his forehead,^{(A) 17} so that no one can buy or sell unless he has the mark: the beast’s name or the number of its name.

¹⁸ This calls for wisdom:^[a](B) Let the one who has understanding calculate^[b] the number of the beast, because it is the number of a person. Its number is 666.^[c]