Q. Why is Sunday the first day of the week? Is it the same in the Old Testament?
A. Throughout history the Sabbath has been the 7th day of the week. It’s the day when God ceased His work of creating and rested (Genesis 2:2-3). On the Hebrew calendar the 7th day is the day we know as Saturday, making Sunday the first day of the week. Most western calendars are laid out the same way.