Did the Roman Catholic Church Institute Sunday Worship?
The Seventh-Day Adventists maintain that it was the Catholic church that changed the day of worship from Saturday to Sunday and enforced the change through a decree issued by Emperor Constantine in 321 AD. This contention is as invalid as the one made by Dan Brown in his book, The Da Vinci Code, when he asserts that the Church did not recognize the divinity of Jesus until Emperor Constantine forced them to do so at the Council of Nicea in 325 AD. In both cases, the action simply codified what was already the accepted belief or practice.
The New Testament attest to Sunday worship in Acts 20:7 and 1 Corinthians 16:2. And the writings of the Church Fathers also confirm that Sunday worship was the accepted practice long before Constantine:
The Epistle of Barnabas (100 AD) — "Wherefore, also, we keep the eighth day with joyfulness, the day also on which Jesus rose again from the dead."
Epistle of Ignatius to the Magnesians (110 AD) — "If therefore, those who were brought up in the ancient order of things have come to the possession of a new hope, no longer observing the Sabbath, but living in the observance of the Lord's Day, on which also our life has sprung up again by Him and by His death."
Justin Martyr in his First Apology of Justin (ca 147 to 161 AD) — "On the day called Sunday, all who live in cities or in the country gather together to one place, and the memoirs of the apostles or the writings of the prophets are read as long as time permits... Sunday is the day on which we hold our common assembly, because it is the day... Jesus Christ our Savior... rose from the dead."
Tertullian in An Answer to the Jews (ca 200 AD) — "The observance of the Sabbath is demonstrated to have been temporary..."