SACRED NUMBERS. – In the primitive mentality, a number assumes a sacred significance insofar as it is linked with the image of objects that provide a frequent occasion for counting. Among groups of lesser culture, the numbers identified by a name do not go beyond ten.
Not all peoples venerate the same numbers as sacred, because their sacredness does not depend on psychological motives, which would be the same for everyone, but on special circumstances that have led various peoples to establish the religious value of certain numbers rather than others. It may nevertheless be affirmed that, above all, observation of the sky and of the great divisions of the universe have determined among many peoples the sacred character of certain numbers. The principal ones are:
ONE. — The basis of numeration, with a predominantly philosophical-mystical significance, from the monad of Pythagoras to the One of Plato and the Neoplatonists.
THREE. - It is par excellence the sacred number in religions and folklore. In Babylon there is the divine triad Amu, Bel, Ea, corresponding to the three great divisions of the world: heaven, earth, and water. Among the Jews, David must choose among three plagues: famine for 3 years, flight for 3 months, or festivals for 3 days. In India, the trimurti—Brahma, Višnu, Šiva—represents the threefold principle of creation, preservation, and destruction. In Greece and Rome, 3 governs the norms of ritual: triple libation, triple pronouncement of sacred words, the 3 animals of the suovetaurilia sacrifice, and triple lustral circumambulation; 3 and multiples of 3 (6 and 9) are the offerings that the Arval Brethren make in the great rite of May; 27 (3 x 3 x 3) are the boys and girls who sing before the temple of Juno Regina on the Aventine in 207 B.C. (Livy, XXVII, 37) and at the Secular Games of 17 B.C. and A.D. 204. In Christianity, apart from the Most Holy Trinity and the mystical value of its exemplarism in the universe, 3 predominates in the liturgy: 3 Agnus Dei, 3 Sanctus, 3 Mea culpa, 3 Domine non sum dignus.
FOUR. – Among the North American Indigenous peoples, 4 has a sacred significance determined by the four cardinal points, to which colors, gods, animals, and fixed qualities correspond. Among the Babylonians, too, 4 symbolizes the 4 regions of the earth. Among the Hebrews, there are 4 rivers of Paradise and 4 days of mourning that the maidens of Israel devote to the memory of Jephthah’s daughter.
SEVEN. - It is par excellence the astrological number, sacred to the Babylonians because of the 7 planets, the 7 evil spirits, the 7 divisions of hell, the 7 levels of the siigurat (temple towers); the 7 repetitions for every rite of enchantment or magic or lustration, etc. Seven is, in short, the number indicating completeness and meaning “everything”; seven times seven is equivalent to “always.” It is also sacred to the Jews, who adopted it especially in apocalyptic literature: the 7 heavens, the 7 rivers of the 7 mountains; and in the liturgy: the 7 altars, the 7 sacred springs, the 7 branches of the candelabrum, the 7 anointings with oil, the 7 pairs of clean animals that entered the ark, etc.
In Hindu mythology there are the 7 oceans, the 7 rsi, the 7 Aditya, the 7 horses of the sun, the 7 wells into which one must look in order to be cured of hydrophobia, etc. In Christianity, too, 7 is a highly symbolic number: the 7 Sacraments, the 7 gifts of the Holy Spirit. Belief in the sacredness of 7 gave rise in the classical period, and prolonged into the Christian period, to belief in the climacteric year—that is, the year of life that is a multiple of 7, especially 49 (7 × 7) and 63 (7 × 9).
DIECI. – It is the sum of two sacred numbers, 3 and 7; 10 are the plagues of Egypt, and 10 the Virgins of the parable; in the Jewish liturgy, there are 10 curtains of the tabernacle, the cherubim of the Temple are 10 cubits high, and there are 10 bronze basins; 10 are the horns of the apocalyptic beast.
DODICI. — This number forms the basis of the numerical system of the Sumerians, which they subsequently transmitted to the Babylonians; there are 12 signs of the Zodiac, 12 months of the year, 12 hours of the day, 12 parts of paradise, 12 tribes of Israel, 12 bronze bulls supporting the great basin of the Israelite sanctuary, 12 loaves of the presentation, and 12 stars around the head of the woman clothed with the sun in the Apocalypse.
FORTY. – This is the number adopted for periods of expectation and penance. 40 are the days of the Flood, 40 the years that the Hebrews spend in the desert, 40 the days spent by Moses on Sinai, 40 the days announced by Jonah for the destruction of Nineveh, 40 the days from the Resurrection to the Ascension, and 40 (instead of 30) are, in the Eastern Church, the days that must elapse before the third commemoration of the dead.
SEVENTY. – It is sacred as a multiple (7 × 10) of 7. 70 the nations in the ethnological table of Genesis, 70 the elders of Israel, 70 the years or weeks of years of apocalyptic literature, 70 (or 72) the disciples of Jesus.
324–64; L. Lévy-Bruhl, Les fonctions mentales dans les sociétés inférieures, Parigi 1910, pp. 204–60; F. Cumont, La triple commémoration des morts, in Acad. Inscript. et Belles Lettres, 1918, p. 278 ff.