Every time we say "Monday" or "Saturday" we are, without knowing it, uttering the name of a planet. The seven-day week used almost everywhere in the world bears the imprint of an ancient astrological order, and the names of the days are one of the few places where traditional astrology still lives, every day, in everyone's language.
From planets to days
In Roman times a week spread in which each day was dedicated to one of the seven visible planets. The order is not random: it derives from the system of planetary hours. Since a day has twenty-four hours and there are seven planets, the planet ruling the first hour of each day moves three places forward in the Chaldean order (Saturn, Jupiter, Mars, Sun, Venus, Mercury, Moon) compared with the previous day. Starting from Saturn, this gives the sequence: Saturn, Sun, Moon, Mars, Mercury, Jupiter, Venus.
The seven-pointed star
If you arrange the seven planets in Chaldean order around a circle and connect them by skipping two positions each time, you draw a seven-pointed star, the heptagram, and the path traced gives back exactly the order of the days of the week. This figure appears in many esoteric diagrams as a visual summary of the bond between time and the sky.
The names in Latin and Italian
| Latin | Planet | Italian |
|---|---|---|
| dies Lunae | Moon | lunedì |
| dies Martis | Mars | martedì |
| dies Mercurii | Mercury | mercoledì |
| dies Iovis | Jupiter | giovedì |
| dies Veneris | Venus | venerdì |
| dies Saturni | Saturn | sabato |
| dies Solis | Sun | domenica |
Two days lost their planetary name in Italian. Sabato comes from the Hebrew shabbat, the day of rest; domenica from the Latin dies Dominica, "the Lord's day", a name that took hold with Christianity. As early as 321 the emperor Constantine had established the "venerable day of the Sun" as a day of rest. The planetary link remains clear in other languages, however: English Saturday and Sunday preserve Saturn and the Sun.
The names in other languages
In the Germanic languages
The English, Germans and Scandinavians replaced the Roman gods with deities of their own pantheon considered equivalent:
- Tuesday, from Tiw, a god of war, like Mars;
- Wednesday, from Woden (Odin), associated with Mercury as guide of souls and lord of speech;
- Thursday, from Thor, the thunder god, like Jupiter;
- Friday, from Frigg or Freyja, goddesses of love and the home, like Venus.
In Sanskrit and the languages of India
The planetary week also reached India, where the days bear the names of the grahas: Ravivara (Sun), Somavara (Moon), Mangalavara (Mars), Budhavara (Mercury), Guruvara or Brihaspativara (Jupiter), Shukravara (Venus), Shanivara (Saturn).
In Japanese
The Japanese names follow the same scheme through the five Chinese elements, which give the planets their names: nichiyōbi (day of the Sun), getsuyōbi (of the Moon), kayōbi (of fire, that is, Mars), suiyōbi (of water, Mercury), mokuyōbi (of wood, Jupiter), kin'yōbi (of metal, Venus), doyōbi (of earth, Saturn).
The fact that such distant cultures adopted the same order shows how powerful and widespread this system has been.
The quality of each day
Tradition attributed to each day the character of its planet, and many customs preserve the echo.
- Monday, day of the Moon: home, family, the rhythms of the body.
- Tuesday, of Mars: courage, physical work, decisions. A common Italian proverb says, "on Venus's day and Mars's day, neither marry nor set out".
- Wednesday, of Mercury: study, writing, trade.
- Thursday, of Jupiter: generosity, legal and spiritual matters.
- Friday, of Venus: affection, art, beauty.
- Saturday, of Saturn: tidying up, recollection, conclusions.
- Sunday, of the Sun: celebration, light, renewal.
A weekly practice
At Studio Esoterico Cornelio a simple exercise is suggested: for one week, devote a minute of reflection each morning to the planet of the day. Ask yourself where, in that day, you can express its best quality: the Moon's care on Monday, Mercury's clarity on Wednesday, Saturn's patience on Saturday. It is a way of turning the ordinary calendar into a path of attention.
In short
- The names of the days derive from the seven traditional planets.
- The order of the week arises from the planetary hours and can be visualised in the heptagram.
- In Italian, Saturday and Sunday lost their planetary names, which English preserves.
- Germanic languages, the languages of India and Japanese follow the same scheme with their own names.
- Each day can be lived as an opportunity to cultivate the quality of its planet.