Ancient Epitome of Canon XXIX.
A Christian shall not stop work on the Sabbath, but on the Lord's Day.
Here the Fathers order that no one of the faithful shall stop work on the Sabbath as do the Jews, but that they should honour the Lord's Day, on account of the Lord's resurrection, and that on that day they should abstain from manual labour and go to church. But thus abstaining from work on Sunday they do not lay down as a necessity, but they add, "if they can." For if through need or any other necessity any one worked on the Lord's day this was not reckoned against him.