This is partly true. Adventist beliefs are based in large part on Ellen White’s understanding of the Bible but she is not the only one.
Just because it is a relatively new understanding of the Bible does not mean it is false, it just means it is new. If you look at the dates involved roughly 1800 years passed between the founding of the Catholic Church and the founding of the Adventist Church. That is alot of years, so why did it take so long to arrive at Adventist beliefs? I’ll start by asking another question, why did it take the reformation roughly 1500 years to get started?
I think it was a combination of things. Bibles were not widely distributed because the technology to print them quickly and cheaply did not yet exist until the late 1400s. This is really the first time ordinary people (non clergy) were able to study the Bible in detail.
Until that time the only view of scripture was Catholic. Not because it was the only possible view but because of the lack of printing technology and the fact that the Church actively discouraged ideas that challenged their view. There were various other groups of believers throughout history but they were never mainstream and never reached the masses. So the late 1400s and early 1500s are really the beginning point for ideas that differ from the Catholic Church.
We are talking only 350 to 400 years after this that the Adventist church formed based on a set of beliefs arrived at upon studying the Bible beginning with the arrival of the moveable type printing press and later the reformation.
Why did it take 400 years after that for the Adventist Church to come along? There were a string of reforms that needed to take place first upon which the Adventist Church built it’s beliefs. For example, if it wasn’t for William Miller’s misunderstanding of scripture and belief that Jesus would return in 1844 the founders of the Adventist Church would not have gone back to their Bibles to see where they had gone wrong and come to understand the Sanctuary in the way we have.
The fact that the Seventh Day Adventist Church was founded in the 1800s doesn’t automatically make us wrong; If we are wrong it is because we have made an error in our understanding of the Bible, the same is true for any denomination including Roman Catholics.
I thank you for your compliment (I think

).
I have never heard the claim that the Adventist Church was founded by Christ and the Adventist Church does not teach that. We can trace our fundamental beliefs back to the Apostles through the Bible but you are correct in saying that some of our prophetic beliefs are unique.
My time debating with all of you here in this thread has caused me re-evaluate and adjust my understanding of some things though particularly dealing with the history of the Catholic Church which I think is your strongest argument. I haven’t seen anything posted that has caused me to say Adventists are wrong though especially as it relates to the Sabbath Day.
I have seen alot of Bible verses being thrown back and forth but nothing definative and in fact it is clear to me that the Biblical evidence is tipped in favor of the Apostles keeping the Sabbath. I’ll grant you that extra-Biblical sources show that worship on Sunday began far earlier historically than I had previously thought but it seems to have been gradual.
The reason this gradual change is relevant is that the change happened after Jesus’ crucifiction. All covenants between God and his people were sealed by the blood of a sacrificial animal. In the case of the New Covenant, the sacrifice was Jesus. If he was crucified before the change of the Sabbath it could not have been changed in the New Covenant.