Cross-references Explore similar Bible verses on Revelation 13:18 in English Standard Version "This calls for wisdom: let the one who has understanding calculate the number of the beast, for it is the number of a man, and his number is 666." Re 17:9 This calls for a mind with wisdom: the seven heads are seven mountains on which the woman is seated; Re 21:17 He also measured its wall, 144 cubits by human measurement, which is also an angel’s measurement.