Gematria

Gematria, singular gematriot, is calculating the numeric equivalent or value of words or phrases by adding the numbers associated with each letter of a particular alphabet, primarily the Hebrew alphabet associated especially with the Torah. In Greek and Hebrew each letter of the alphabet doubles as a number. Hebrew letter calculation is gematria. Greek letter calculation is also commonly called gematria, but is more properly called isopsephy.

The most famous gematria calculation is the human number of the Beast in the Book of Revelation in the Holy Bible.
Revelation 13:18

“

Here is wisdom. Let him that hath understanding count the number of the beast: for it is the number of a man; and his number is Six hundred threescore and six. (KJV)

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See Numerology.