Day of Worship

"All mankind may be saved through the atonement of Christ and by obedience to the laws and ordinances of the gospel; these include faith in Christ, repentance, baptism by immersion for the remission of sins, the laying on of hands for the gift of the Holy Ghost, and the observance of the Lord's Supper each Sunday."

Handbook of Denominations, p.167

Sunday worship has its origin in the Roman Catholic Church. It was inherited and retained by the Protestant churches after the Reformation. See "Day of Worship--Roman Catholic" for details.