Gematria and isopsephy: when letters become numbers
Greek isopsephy and Hebrew gematria: the Pompeian graffito of the number 545, Nero in Suetonius, the 666 of Revelation and the 318 servants of Abraham.
In antiquity many languages had no numerals separate from their letters: in Greek and Hebrew every letter of the alphabet also had a numerical value. From this simple convention a fascinating practice arose. By adding up the values of the letters in a word one obtained a number, and two words with the same value could be regarded as bound by a hidden relationship. The Greeks called it isopsephy, «equality of value»; in the Jewish tradition it took the name gematria.
A love game at Pompeii
The Greek alphabetic number system spread widely in the Hellenistic period. As so often, the liveliest evidence comes from everyday life. Among the graffiti of Pompeii there is one, written in Greek, which says: «I love her whose number is 545». The author thus hid his beloved's name behind a figure, leaving it to knowing readers, or to the woman herself, to decipher it.
Isopsephy could also serve political satire. Suetonius, in his life of Nero, reports that after the death of Agrippina a Greek line circulated according to which Nero's name had the same numerical value as the phrase «killed his own mother». It was a sharp and almost anonymous way of voicing an accusation that could not be spoken openly.
The number of the beast
The most famous case of a symbolic number in ancient literature is found in the Revelation of John. In chapter thirteen the text invites whoever has understanding to calculate the number of the beast, which is «the number of a man», and gives it as 666. Many modern scholars believe it refers to Nero, obtained by transcribing his name in Hebrew letters, but the interpretation remains debated.
By the end of the second century Irenaeus of Lyon knew that some manuscripts gave the variant 616, and he discussed it. A papyrus fragment from Oxyrhynchus, published in the early 2000s, confirms that this variant really circulated. In the following centuries the number became the object of countless attempts at identification, often tied to the religious and political quarrels of the moment.
Gematria in the Jewish tradition
In rabbinic literature gematria appears as one of the methods of interpretation. A saying preserved in the Sayings of the Fathers, attributed to Rabbi Eliezer ben Hisma, describes it, together with astronomical calculations, as a seasoning of wisdom: not the heart of study, but an ornament. The Talmud suggests, for instance, that the 318 servants of Abraham mentioned in Genesis correspond to the value of the name of his servant Eliezer.
Christians read the same number differently: the Epistle of Barnabas, from the second century, saw in it, in Greek, the sign of the cross and the initials of Jesus. In the Middle Ages gematria developed greatly among the Jewish pietists of Germany, such as Eleazar of Worms, and in Kabbalah, which made it an instrument of meditation on the divine names.
Gematria and isopsephy show how writing could be read on several levels. Behind every word lay a number, and behind every number a possible link with other words: a web that joined play, exegesis and the search for the hidden meaning of things. It is a web that readers of every age have continued to weave.