Weekends and Religious Services

Saudi Arabia is moving from a Thursday-Friday to a Friday-Saturday weekend:

Saudi Arabia, the biggest Arab economy, had been the only Gulf Arab state to have a Thursday-Friday weekend after Oman shifted to a Friday-Saturday weekend last month.

A statement on national Saudi news agency SPA said the change, decreed by King Abdullah, will take effect as of this weekend, "for the sake of putting an end to the negative effects and the lost economic opportunities consistently associated with variation based on work days between local departments, ministries and institutions and the regional and international counterparts".

In an article on the origins of Friday worship among Muslims, S.D. Goitein revealed a bit of the history of two-day weekends in monotheism.  What he found is that with work forbidden to Jews on Saturday, the pattern that developed in rural Jewish areas, including in Arabia, was too work all week producing whatever you produced, and then have Friday as a market day to sell your wares and buy what you needed in advance of the Sabbath.  When Christianity moved its day of rest to Sunday, the market day got moved to Saturday.  In the historically Jewish Medina, Muhammad preached and handled community affairs at the Friday markets, and thus when later Muslims were formally organizing the tenets of their faith, they made that the day of communal worship, though since it was not a day of rest I don't know if there was a tradition of Thursday markets underlying the Thursday-Friday weekend tradition.