“I saw that God had not changed the Sabbath, for He never changes. But the Pope had changed it from the seventh to the first day of the week: for he was to change time and laws.” Ellen G. White, A Word to the Little Flock, “A Vision, April 7, 1847”, p. 18.
“In a view given June 27, 1850, My accompanying angel said, “Time is almost finished. …”The Pope had changed the day of rest from the seventh to the first day of the week.” Ellen G. White, Early Writings, “Mark of the Beast”, p. 65.
It is a fact that Ellen G. White, the founder and prophetess of Seventh-day Adventism, taught that the Papacy (the Roman Catholic Church) changed the Sabbath by transferring its sanctity to the Sunday. Her book, The Great Controversy, has that theme as its central motif.
Not only did she teach these things, but she claims that God showed her this in vision.
The Eastern Orthodox Church existed for centuries before the ascendency of the Roman Catholic Church, and had authority over the Roman church in every aspect. In fact, the Roman Church was supported by the Eastern church during those early years, they sent them missionaries and deposed their bishops from time to time.The first seven Church councils were dominated by the Eastern churches, held in Greek (not Latin), and the Bishop of Rome did not even attend them all (such as the council of Nicea).
The Schaff-Herzog Encyclopedia, under “Eastern Chuch”, has this entry: “This Church is the oldest in Christendom, and for several centuries she was the chief bearer of our religion.”
The Eastern Orthodox Church has historical records that date back to the first century, the time of the apostles. They claim that Sunday has been the only day of Christian worship since the resurrection. Read this from an Orthodox Bishop in America:
Question Number 10:
Is it the Orthodox view that Sabbath has been transferred to Sunday? What is the Orthodox view on Sabbath?
ANSWER:
The Orthodox believe that Sabbath is Saturday (to this day, the Greek word for Saturday is pronounced ‘sabbado’ – as is the case in many other languages). Hence, Saturday is the old Sabbath and Sunday is the Lord’s Day or the Day of Resurrection. In the Orthodox tradition, Saturday always has the feastly character of the Jewish sabbath; it is never a strict fasting day. Moreover, it has always been the liturgical practice to serve Divine Liturgy both on Sabbath and the Lord’s Day, and this remains the case in Orthodox monasteries. However, Christians are not under the Law and they are not subjects of the Old Creation. The old Sabbath was the seal of the old creation, whereas Sunday is seal of the New Creation, the first or eighth day. For this reason, Gentile Christians have never been bound by Sabbatical laws on the old Sabbath. (Fr. Laurent, OrthodoxAnswers.com)
539. Since when do we keep the Day of the Resurrection?
From the very time of Christ’s resurrection.
Solus Christus | In Christ Alone 
As a former SDA for over 25 years, I am familiar with Ellen G. White and her many “prophecies.” You are correct that the Sabbath is a major part of the SDA Church. In fact, I would call it a “pillar” of the SDA Faith as a whole.
The Apostle Paul preached to Jews and Gentiles alike on the Sabbath, according to various passages in the Epistles. In addition, he preached at other times as well.
Of course, the pope and the Catholic Church are viewed as the “enemy” to the “remnant church” as the SDA’s call themselves. The pope is “The Beast” of Revelation.
I have attempted to reach current and former SDA’s alike with many posts on Sabbath and Ellen G. White. However, she is so solidly part of SDA Theology, to discredit even her in an area as strong as the Sabbath, risks deflating Adventism as a whole.
I like your article, well done!
-Dave
Another SDA “pillar” is Daniel 8:14 unfullfilled and reserved for 1844.
The SDA “jesus” knew it was only for 1844, but taught orherwise in Matt 5:17, Matt 11:13, Luke 21:22 and John 19:28. In other words a liar. Satan is a liar. Do the spiritual math to see that SDA’s have been tricked into worshipping satan.
More sabbath canceling sin. They are idolators and utter liars who keep nothing holy, James 2:10. Game over, sabbath pretenders!