First: WHAT IS GEMATRIA?
Answer: interpreting the scriptures by computing the numerical value of words, based on those of their constituent letters.
Greek and Hebrew did not use a different system for their alphabets and their numerals, but the letters of the alphabet played double duty, so that each letter had a numerical value. One pay-off of that system was that every word had a numerical value, discovered simply by adding up the letters. In Greek, for example, the six letters in the name Jesus, Ιησους , add up to 888.
Or another example: in Hebrew, the three letters in the name “David” (ancient Hebrew did not have vowels, only consonants), D-V-D were worth 4-6-4, so that the name added up to 14. That may have been significant for the genealogy of Matthew’s Gospel (Matthew 1:1-17), since, as Matthew presents it, Jesus, the “son of David” had a genealogical tree that can be organized around the number 14: between the father of the Jews, Abraham, and the greatest king of the Jews, David, was 14 generations (Matthew tells us); between the greatest king of the Jews and the most significant disaster of the Jews – the Babylonian exile – was 14 generations; and between the most significant disaster of the Jews and the messiah of the Jews, Jesus, was 14 generations. 14-14-14. This may seem like a miracle. And for Matthew it probably was. *Possibly* (this is one theory) he latched on to 14 because it is twice the perfect number, 7 (so doubly perfect). Or possibly it is because this is the genealogy of the son of David, whose number is 14. (In either case, the reality is that to get to 14-14-14 Matthew had to drop several names out between Abraham and David; moreover, unfortunately, in the last set of 14 there are in fact only 13 generations named!)
An even more clever use of numerology is in the ….
An even more clever use of numerology is in the non-canonical letter of Barnabas, one of the Apostolic Fathers. I think we may all be glad that Barnabas did not finally make it into the canon of Scripture as one of the books of the New Testament, even though there were church writers who thought it *should* be included (it can be found, for example, in the famous Codex Sinaiticus from the fourth century, as one of the books of Scripture). It is a virulently anti-Jewish book. Written around 130 CE, the entire point of the letter is that the Jews have rejected God going all the way back to when Moses was given the Law on Mount Sinai, which is why he smashed the two tablets of the law into smithereens: that showed that the Jewish people had broken/smashed the covenant just as soon as they got it. And since they rejected God and his covenant, God rejected them. They are not the people of God and never have been. It is the Christians who are the people of God.
Because the Jews rejected God, they never understood the laws that Moses gave them. The Jews wrongfully imagined that God meant these laws – for example about keeping the Sabbath and eating kosher foods – to be kept literally. For Barnabas that’s ridiculous. What the Jews never understood was that God meant the laws to be taken figuratively.
That is true, for example, of the law of circumcision. The Jews are foolish to think that God wants his people to cut off the foreskin from the penises of their newborn boys. Circumcision is not about the literal cutting of the flesh. Then what is it about? It’s about the cross of Jesus as the way of salvation. And always was.
How does Barnabas get to that somewhat unusual interpretation? He points out that in the Hebrew Bible Abraham, the father of the Jews, is the first who is ordered to perform circumcision (Genesis 17). And it is Abraham who brought salvation to his nephew Lot, who had been taken captive by an army of hostile forces. How did Abraham do that? He took 318 servants with him, whom he had circumcised (says Barnabas), and with that small (circumcised) army, set Lot free.
But why were there 318 of them? Barnabas indicates that it was because of the symbolic value of that number. In Greek, the language in which Barnabas was reading the Scriptures, 318 is made by the letters tau-iota-eta, like this: Τ-Ι-Η. That is significant for Barnabas. Highly significant. What is the tau in the shape of? A cross. And what do iota-eta signify? As it turns out, they are the first two letters in the name Jesus, ΙΗΣΟΥΣ. And so 318 refers to the “cross” of “Jesus.” That is how the father of circumcision brought salvation to his nephew Lot. The people of God are not those who have their penises mutilated. They are those who believe in the cross of Jesus. Jews never understood that, and so are lost. Only the followers of Jesus understand it.
And it was all written in the Jewish Bible. Which means Jews never understood their own Scriptures. For Barnabas, the Old Testament is not a Jewish book and was never meant to be. It is a Christian book, and only those who are followers of Jesus can understand its real, symbolic, and true meaning.
Aren’t numbers wonderful?
Note: the above is culled from Bart Ehrman's Blog. http://ehrmanblog.org/creative-uses-of-numbers-in-scripture/