Week: Encyclopedia II - Week - Later use of the week

Week - Later use of the week

Various groups of citizens of the Roman Empire adopted the week, especially those who had spent time in the eastern parts of the empire, such as Egypt, where the 7-day week was in use. Contemporaneously, Christians, following the biblical instruction, spread the week's use along with their religion.

As the early Christians evolved from being Jewish to being a distinct group, various groups evolved from celebrating both the Jewish Sabbath (Saturday) and the first day or the Lord's Day (Sunday), to celebrating only Sunday. See: Sabbath (Christian); Shabbat (Jewish).

In the early 4th century, the Roman Emperor Constantine regulated the use of the week due to a problem of the myriad uses of various days for religious observance, and established Sunday as the day for religious observance and rest for all groups, not just those Christians and others who were already observing Sunday.

The Jews of the 4th century retained their tradition of Saturday observance, by then 800 to 1700 years old, and continue to do so. Later, after the establishment of Islam, Friday became that religion's day of observance.

The 7-day week soon became a practice among Christians, Jews, and Muslims. Following European colonization and the subsequent rise of global corporate business, the 7-day week has become universal in keeping time, even in cultures that did not practise it before. Because of the two-day weekend, some modern calendars end the week on Sunday and begin it on Monday. The international standard ISO 8601 also defines Monday as the first day of the week. In practice, this means that calendar formats disagree, and that "next week" said on Sunday means "the week beginning tomorrow".

In that international standard, the "first week of the year" is that week which includes the first Thursday of the year. This way the first week of the year does not start with a long weekend (Friday to Sunday), as the New Year's Day itself is a holiday in many countries.

Adapted from the Wikipedia article "Later use of the week", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki