Sabbatarianism in the context of "Sunday School"

Church attendance is a central religious practice for many Christians; some Christian denominations require church attendance on the Lord's Day (Sunday).

In addition to being based upon the spirit of the Ten Commandments ("Remember the Sabbath day, to keep it holy"), the importance of church attendance in Christian theology is delineated in Hebrews 10:25, which implores the believers: "Let us not neglect our church meetings, as some people do, but encourage and warn each other, especially now that the day of his coming back again is drawing near." Certain early Christian saints emphasized the necessity of church attendance for the continuance of the faith, such as John Climacus, who declared that "a sure sign of the deadening of the soul is the avoidance of church services." The Lutheran theologian Balthasar Münter [da] stated that church attendance is the "foundation for the Christian life" as "the Christian Bible and the sacraments provide the framework for the faith"; he also states that it is important for believers because it aids in the prevention of backsliding, as well as offers "the company of other believers". The Catholic Church teaches that on Sundays and other holy days of obligation, the faithful are required to attend Mass. The Westminster Confession of Faith held by many Reformed Churches teaches first-day (Sunday) Sabbatarianism and the duty of church attendance on this day. Similarly, Methodist Church also requires attending "the public worship of God".

Subbotniks (Russian: Субботники, IPA: [sʊˈbotnʲɪkʲɪ], "Sabbatarians") is a common name for adherents of Russian religious movements that split from Sabbatarian sects in the late 18th century.

The majority of Subbotniks were converts to Rabbinic or Karaite Judaism from Christianity. Other groups included Judaizing Christians and Spiritual Christians.