William Miller misinterpret the 2300 day prophecy but it all worked out for the Good.
A revival was started and faith was tested. People went back to their Bibles to study the word.
Here is my understanding of Seventh-day Adventists, and I am open to correction. I also understand that, as with Protestantism generally, there may be differences among individuals and groups who identify with that tradition.
As I understand it, Seventh-day Adventism is first and foremost a Christian movement that affirms the central truths of the faith:
First, that the Scriptures are the inspired Word of God, and that the God of Abraham, Isaac, and Jacob is the one true God.
Second, that Jesus Christ, the Jewish Messiah, came into the world to give Himself as the sacrifice for sin. He is Lord, Savior, and the only means of salvation.
Third, that the New Testament is also the inspired Word of God and gives the apostolic witness to Jesus Christ, His death, resurrection, heavenly ministry, and promised return.
Now, beyond those central beliefs, Seventh-day Adventists hold other doctrines and interpretations, including their understanding of baptism, the Sabbath, the state of the dead, the sanctuary, the judgment, and prophecy. Some of those interpretations I may agree with, and some I may question. But I would not place every prophetic interpretation or denominational practice on the same level as the gospel itself.
They are also no different from most Protestant groups in this sense: they have spent much time and effort attempting to read, study, and properly interpret Scripture. And I think we should all admit that interpreting Scripture, especially prophecy, is one of the most difficult tasks before us. There is no complete consensus even among brilliant scholars, theologians, pastors, and students of the Bible on many of the most important prophetic passages.
For example, the Millerite movement expected the return of Christ in 1844. They were wrong. That error came from an incorrect interpretation of Daniel’s 2,300-day prophecy, combined with a very sincere and intense hope that they would soon see their Lord face to face. Later, Seventh-day Adventists reinterpreted 1844 in connection with Christ’s heavenly sanctuary ministry rather than His visible return to earth.
Now, one may reject that interpretation. One may argue that Daniel 8 has been misunderstood. One may believe their prophetic framework is wrong in important ways. But that kind of interpretive error is not the same thing as claiming divine authority to change God’s commandments, forgive sin by priestly office, exalt an earthly religious head as God’s representative over the whole church, or place human tradition above the Word of God. That is the distinction I am trying to make.
If we were to place the central Christian beliefs of Seventh-day Adventists on one side of a page, and then place the major claims of the Roman Catholic system on the other, which one departs more seriously from the commands of Christ and the teaching of the apostles?
I do not see Seventh-day Adventists teaching an infallible pope. I do not see them claiming one earthly bishop has universal authority over the church. I do not see them teaching prayers to Mary and the saints. I do not see them promoting image veneration, indulgences, purgatory, priestly absolution, or salvation through submission to the Roman sacramental system. I do not see them claiming that church tradition can stand alongside or above Scripture.
Those are not minor differences. Those are massive departures.
So, in my opinion, an incorrect interpretation of the 2,300 days in Daniel 8 is not on the same level as a religious system that claims papal supremacy, priestly power to forgive sins, authority over God’s commandments, prayers to Mary and saints, and salvation mediated through the institution and its sacraments.
One is an interpretive mistake concerning prophecy. The other is a system that has claimed powers and honors that belong only to God. That does not mean every Adventist interpretation is correct. It does not mean every SDA teacher is right. It does not mean we should accept their prophetic system without testing it. Everything must be tested by Scripture. But we should be careful not to place every religious error in the same category. A mistaken interpretation of Daniel is one thing. A system that exalts human authority over Christ, Scripture, and conscience is something far more serious.
That is why I see a major difference between a Protestant group that may be wrong on certain prophetic interpretations and a religious system that, over centuries, has buried the simplicity of the gospel beneath papal authority, sacramental control, prayers to saints, Marian devotion, image veneration, purgatory, indulgences, and tradition elevated above Scripture. The issue is not whether any denomination is perfect. None is. The issue is whether its errors are interpretive errors made while trying to follow Scripture, or whether the system itself claims authority that Scripture never gives to any man or institution.
Finally, on a specific note, if one were to try to interpret how the 2300 days prophecy speaks TO THE COMING MESSIAH (His first arrival), and not to a historic or secular event or even a heavenly event in the future (in relation to the time of the cross), they would indeed find its true prophetic meaning. Afterall, wouldn't it seem appropriate that the prophecies in Daniel should pretain to the most important event in the history of mankind - the arrival of the Messiah?