Day One Christian Ministries is a United Kingdom-based Christian organisation which lobbies for no work on Sunday, the day that many Christians celebrate as the Sabbath, a day of rest — a position based on the fourth (by the Hebrew reckoning) of the Ten Commandments. Originally founded in 1831 as the Lord's Day Observance Society (LDOS), Day One incorporates the former LDOS, Day One Publications (publishing arm) and the Daylight Christian Prison Trust.