But I will give a very brief and incomplete history of how this Sunday "sabbath" issue grew up in America and why Seventh-day Adventists can find a whole slew of writings they quote in their literature that back up Catholics calling Sunday, "the Sabbath."
First, through the centuries, scholars--all theologians--have seen the similarities in holy days. There are similarities in the high holy days that occur once a year in Lev. 23 to the sabbath that occur weekly. In fact, the Passover was called a "sabbath" just as the 7th day was called a Sabbath, though they were not commemorating the same event. The Passover was a holy day just as the seventh-day was a holy day, but they were very different in that one pointed to the Promised Land and the other pointed to Creation. We have holidays in America and are free to call Christmas a holy day and somehow that is not confused with Easter. It's similar to the way Catholic theology treats the Lord's Day and Sabbath.
Okay... so, understanding this, I jump to 19th century United States.
America had been very anti-catholic. Many early colonies did now allow Catholics to live there. The KKK's targets were both blacks and Catholics. The Catholic Church was attempting to survive by proving to Protestants we were not the great evil thing it was being portrayed as. Public and private debates erupted.
There seemed to be one point upon which the Protestants could not answer the Catholics. Catholics asked them why Protestants went to church on Sunday when there was nothing explicit in scripture that commands Christians to worship on Sunday. It was their "gotcha" moment in all exchanges. The point was that Protestants unknowingly accepted the authority of the Catholic Church by going to church on Sunday. To this day, the same argument is used by Catholics to Protestants who deny that the Catholic Church has authority. Why do you go to church on Sunday?
...... crickets......
Because the Catholic Church sees similarities in the Lord's Day and the holy seventh-day of the commandments, Catholics are free to use those similarities.
However, the Catholic Church never changed the Sabbath to Sunday. Sunday is the Lord's Day. It is the first day and the eighth day---it is not the seventh day. If one goes to Rome, one will hear anyone speaking Italian or Latin refer to the first day of the week as "The Lord's Day" and the seventh day of the week as "The Sabbath." There is not a transference. Sunday gets its holiness from being the great day of the Son of God gave His life to save the world. Sunday doesn't need to borrow its holiness from Sabbath. Indeed Sabbath derives its holiness because it foreshadowed the holiest day of all time.... the day heaven and earth met in a cosmic battle for our souls. And there was never a doubt as to who would win. Jesus won. And each Sunday we are celebrating that.
The sabbath was just like John the Baptist when he said something similar to, "I must grow lesser that Jesus may grow greater."
American Catholics have used the Sabbath/Sunday as a survival issue so that the could end the attacks on Catholics. They just have never taken the time to explain the theological nuances of the Lord's Day. And that has caused untold misunderstandings with Adventists.
