First-day Sabbath

Sabbath in Christianity is the inclusion or adoption in Christianity of a Sabbath day. Established within Judaism through Mosaic Law, Christians inherited a Sabbath practice that reflected two great precepts: the commandment to "remember the sabbath day, to keep it holy" and God's blessing of the seventh day (Saturday) as a day of rest in the Genesis creation narrative. The first of these provisions was associated in Judaism with the assembly of the people to worship in the Temple in Jerusalem or in synagogues.

The position now dominant in Western Christianity is that observance of the Lord's Day, Sunday, supplanted or superseded the Sabbath commandment in that the former "celebrated the Christian community's deliverance from captivity to sin, Satan, and worldly passions, made possible by the resurrection on the first day of the week." Early Christians observed the seventh day with prayer and rest, but they also gathered on the first day. By the 4th century, Christians were officially observing the first day, Sunday, as their day of rest, not the seventh.

Beginning about the 17th century, a few groups of Protestants arose to take issue with some of the practice of the churches around them, sometimes also questioning the theology that had been so widely accepted throughout 16 centuries. Mostly Sabbatarians, they broke away from their former churches to form communities that followed Sabbath-based practices that differed from the rest of Christianity, often also adopting a more literal interpretation of law, either Christian or Mosaic.

A sabbatarian movement within Oriental Orthodoxy began in the 12th century in Ethiopia and gained momentum in the 13th, eventually establishing itself as the norm in that region. The modern Orthodox Tewahedo churches observe a "two-day Sabbath", including both Saturday and Sunday.

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