Thoth, the ibis god of the Moon, writing and the reckoning of time
Thoth, the ibis-headed Egyptian moon god: Hermopolis, his role in the judgement of the dead, Plutarch's myth of the five added days and Hermes Trismegistus.
If for the Egyptians the Sun was the king of the sky, the Moon was his scribe and his accountant. Thoth, in Egyptian Djehuty, is the god who measures, calculates and records: inventor of writing according to tradition, lord of wisdom and keeper of the calendar. His bond with the Moon is not a late addition but an ancient feature, visible in the images that show him with the lunar disc and crescent above his head.
The ibis and the baboon
Thoth was represented in two animal forms. The better known is that of the ibis, or of a man with the head of an ibis, whose curved beak has often been compared to the crescent of the Moon. The other is that of the baboon, an animal the Egyptians watched as it seemed to greet the rising of the heavenly bodies with cries. Both forms appear with the lunar disc, and sometimes the baboon sits composed with its hands on its knees.
His main cult centre was Khemenu, the city the Greeks called Hermopolis Magna, in Middle Egypt, near modern el-Ashmunein. In the nearby necropolis of Tuna el-Gebel underground galleries have been found containing an enormous number of mummified ibises and baboons, offered by pilgrims in the later periods. The same necropolis holds the tomb of Petosiris, high priest of Thoth, who lived at the end of the fourth century BC.
The scribe of the judgement
In funerary texts Thoth plays a central role. In the judgement scene described in chapter 125 of the Book of the Dead, the heart of the deceased is weighed on the scales against the feather of Maat, truth and cosmic order, and Thoth records the result on a scribe's tablet. His task is not to judge but to bear exact witness, like the Moon that marks time without ever erring.
The first month of the Egyptian civil calendar bore his name, Thoth, and the Egyptians credited him with knowledge of astronomical reckoning. He was called lord of time and reckoner of years, titles that reflect a concrete observation: the lunar month was one of the first tools with which humans measured the passing of days.
The game of dice with the Moon
Plutarch, in the treatise On Isis and Osiris, reports a tale explaining the origin of the five days added at the end of the Egyptian year of 360 days. The Sun had cursed the goddess Nut, preventing her from giving birth in any month of the year. Hermes, that is Thoth for the Greeks, then played at dice with the Moon and won from her the seventieth part of each of her lights, from which he made five new days. On them Osiris, Isis and the other children of Nut were born.
The Greek identification of Thoth with Hermes had lasting consequences. From it arose the figure of Hermes Trismegistus, the «thrice greatest», to whom were attributed the treatises of the Corpus Hermeticum, composed in Greek in the first centuries of the Christian era. Marsilio Ficino translated them into Latin in Florence in 1463, and through him the lunar god of Hermopolis entered the heart of European Renaissance esotericism.