Although Sunday (as the Lord’s Day) was understandably known as the first day of the week, it was strangely embraced by Christians as “the eighth day.”  This notion of an eighth day (where Sunday circles around upon itself) reflects the special observances which Christians recognized in other specific days of the week.  Friday and Saturday, in particular, were given emphasis.  Because Friday was the day of Jesus’ death, it became the weekly approach to the Lord’s Day.  Fasting on Friday was altogether proper and fitting to remind Christians of the Christ’s sacrifice.  Saturday (the day in the tomb) was a day of quiet spiritual preparation for the Sunday feast.

Just as the First Day begins and sanctifies the week, so also the Lord’s Day has priority over and determines the Church Year (also known as the “liturgical year”).  It is usually taken for granted that Christmas and Easter are the primary feasts of the church.  But, in fact, the primary Christian feasts must occur weekly, not annually—they occur every Lord's Day, not Christmas and Easter.  The weekly feast of the church takes precedence over any annual festival.