History of the Weekdays

By the third century the seven-day week had become common in private life throughout the Roman Empire. Each day was dedicated to one of the seven planets. Those seven, according to the current astronomy, included the sun and the moon, but not the earth. The order in which planets governed the days of the week was: sun, moon, Mars, Mercury, Jupiter, Venus, and Saturn. This order was not that of their then supposed distance from the earth, which was the "normal" order in which Dante, for example, later described the zones in the heavens, and in which the names of the planets were recited in the schools down to the time of Copernicus.

Our familiar order of the names for the days of the week came from this order of the planets that the Romans thought "governed" the first hour of each day in turn. The astrologers of the day did make use of the "order" of the planets according to their supposed distance from the earth, to calculate the "influence" of each planet on worldly affairs. They believed that each planet would govern an hour, then in the next hour would give way to the influence of the next planet nearer the earth, and so on through the cycle of all seven planets. After each cycle of seven hours, the planetary influences would begin all over again in the same order. The "governing" planet for each day, then, was the planet that happened to preside over the first hour of that day, and each day of the week thus took its name from the planet that governed its first hour. The result of this way of calculating was to name the days of the week in their now familiar order.

The days of our week remain a living witness to the early powers of astrology. We easily forget that our days of the week really are named after the "planets" as they were known in Rome two thousand years ago. The days of the week in European languages are still designated by the planets' names. The survival is even more obvious in languages other than English.

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When peoples have tried to extinguish ancient idolatry, they have replaced the planetary names with simple numbers. So the Quakers call their days First Day, Second Day, and so on up to Seventh Day. They hold their religious meetings not on Sunday but on First Day. In modern Israel, too, the days of the week are given ordinal numbers.

One of the more unexpected examples of the power of the planetary idea is the Christian change of the Sabbath from Saturday, or Saturn's day, to Sunday, or Sun's day. When Christianity first took root in the Roman Empire, pious Church Fathers worried over the survival of the pagan gods in the names of the planets that governed the Christian week. The Eastern Church had some success in exterminating this pagan influence: the names of the days in both modern Greek and Russian ceased to be planetary. But Western Christianity proved more willing to turn Roman beliefs and prejudices to their own purpose. The Church Father Justin Martyr (c. 100-c. 165) shrewdly explained to the Emperor Antoninus Pius and his sons (c. 150) why the Christians chose their particular day for Gospel reading and to celebrate the Eucharist. "It is on what is called the Sun's day that all who abide in the town or the country come together. . . . and we meet on the Sun's day because it is the first day on which God formed darkness and mere matter into the world and Jesus Christ our saviour rose from the dead. For on the day before Saturn's day they crucified him, and on the day after Saturn's day which is the Sun's day he appeared to his apostles and disciples and taught them."

Saturn's day, the traditionally unlucky day when the Jews found it wise to abstain from work, somehow remained the pivot around which the weekly auspices would revolve. But there were still other influences. The Mithraists, followers of the Persian mystery religion who worshipped the sun-god Mithras, which was one of the strongest competitors of Christianity in the Roman Empire, adopted a seven-day week. They naturally felt special reverence for what everybody then called the Sun's day.

The Christians fixed their Lord's day, then, so that every week's passing would relive the drama of Jesus Christ. By taking Communion, every Christian would somehow become one of the Disciples at the Last Supper. The script for this mystic drama was, of course, the liturgy of the mass. The Eucharist, like the other sacraments, became a repeat performance of a crucial symbolic event in the history of the Church. What a happy coincidence that the Sun's day was already known as a day of joy and renewal! "The Lord's day is reverenced by us," a Church Father, Maximus of Turin, explained in the fifth century, "because on it the Savior of the world like the rising sun, dispelling the darkness of hell, shone with the light of resurrection, and therefore is the day called by men of the world the Sun's day, because Christ the sun of righteousness illumines it." The Sun's day, like the first David, prefigured the dazzling light of the sun in the true Savior. The Church Fathers made this coincidence further evidence that the world had long been preparing itself for the Savior's coming.

From astronomy and astrology to religion, complete with superstitions.