Gematria is a Jewish form of numerology in which the letters of the Hebrew alphabet are substituted with corresponding numbers. The first ten letters are given number values that increase consecutively from 1 to 10. The next eight letters are given number values that increase by a factor of ten from 20 to 90. The final four letters are given number values that increase by a factor of one hundred from 100 to 400. In Hebrew, gematria is often used as an alternative to Arabic Numerals when recording numbers. Hebrew dates are generally written using gematria.
In addition to its use as a number system, gematria can also be used as a form of bibliomancy in order to obtain a more spiritual understanding of Biblical texts. While many scoff at using this "cute word play" as a means of explaining the Bible, many Kabbalists -- Jewish mystics who find great power in the spirituality of words -- see it as a valid form of Biblical interpretation. An example of Biblical exegesis using gematria can be found in the fifth of the Ten Commandments (Exodus 20:12) where the Children of Israel are instructed to "honor thy father and mother". How does one honor his parents? By examining the gematria of the Hebrew word for honor, כבד (kabed) we find that it has the value of 26 ([כ=20, ב=2, ד=4, [20+2+4=26). The gematria of the thematically similar word for love אהבה (ahavah), is 13 ([א=1, ה=5, ב=2, ה=5, [1+5+2+5=13). Because the gematria of כבד (kabed) is double that of אהבה (ahavah), it was concluded that one honors his parents by showing them a double portion of love.