The Observance of the Lord's Day

As the Sabbath was instituted to celebrate the old creation, so the Lord’s day celebrates the New Creation. Throughout this age, the most Spirit-filled, devout believers to whom the will of God has been clearly revealed have kept the Lord’s day apart from any sense of responsibility to keep the seventh day. It is reasonable to suppose that had they been guilty of sabbath breaking, they would have been
convicted of that sin.
https://plymouthbrethren.org/article/1588