First day Sabbatarianism

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 and declared as made for man by Jesus. 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The position now dominant in Western Christianity is that observance of the Lord's Day, Sunday, supplanted or superseded the Sabbath commandment in that the former "celebrated the Christian community's deliverance from captivity to sin, Satan, and worldly passions, made possible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.

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. Influenced by Puritan ideas, the Presbyterian and Congregationalist, as well as Methodist and Baptist Churches, enshrined first-day Sabbatarian views in their confessions of faith, observing the Lord's Day as the Christian Sabbath.

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