The Adventist Gospel has been branded as the Three Angels Messages (or Everlasting Gospel) using language from Revelation 14:6-12. They believe the fullness of the Gospel fell away and God raised their movement up to restore it. While the biblical text says very little that is explicit, the Adventist Church, by way of Ellen G. White, believe they have inspired insight to the true meaning of any biblical text. The Second Angels Message is claimed to be derived from Revelation 14:8
They interpret this Second Angels Message as a call for Christians attending non-Adventist churches to leave those churches and join the one true, last day remnant—the Seventh-Day Adventist Church—and Ellen G. White claimed, in multiple places, that the early SDAs believed this prophecy was fulfilled in 1844 when some Christians left their churches to unite with the Millerite movement.
The churches that rejected William Miller’s fanaticism about the imminent return of Jesus were labeled as “Babylon”, and Ellen White claimed they were rejected by God for rejecting William Miller’s message. A message that was not only completely wrong, but one that Miller himself eventually admitted to being false. Since 1844, all non-Adventist churches are supposedly “rejected” and the Holy Spirit has been withdrawn from them.
She also claimed that God showed her that, because the Christian church rejects their erroneous teaching of the investigative judgement, Christians in non-SDA churches cannot be benefited by Christ’s intercession, their prayers are useless, and Satan is now in control of them. Furthermore, she claimed to also be shown that their profession, their prayers and their exhortations, are an abomination in the sight of God.
This means any sort of revival that has taken place since this time has been a charade and a facade. God hasn’t been behind any of it, all of the professed believers who have come from these revivals have been duped by Satan and they aren’t really Christians because Satan has actually taken control of non-SDA local churches.
The emphasis and focus of this Second Angels Message is on this term Babylon—which they believe refers to the Mother Harlot of the Roman Catholic Church and her daughters (the Protestants). This is why they see the Second Angels Message as having to do with calling Protestants out of their churches which have supposedly fallen and become apostate. The Mother Harlot of Revelation 17 is supposedly Rome and her daughters that are drunk on her doctrinal errors are the apostate Protestant Churches. The chief of which, they believe, to be the immortality of the soul and going to church on Sunday.
It’s important to remember that this is a part of the Adventist Gospel. One must leave their Protestant Church (or any other church) and join theirs—the last day remnant who supposedly keep all the commandments of God—or else the wrath of God and plagues will be poured out on you. But this isn’t the Gospel. The power of God unto salvation (Romans 1:16) is not that you must leave your protestant church and join Adventism. That isn’t what Jesus Christ revealed to the apostles as the one true Gospel (Galatians 1:6-9). The Gospel is the good news about salvation through the Person and work of Jesus, not joining a 19th century fringe movement (among a host of other things they claim).
It is because of this (and a number of other reasons) that the Adventist Church teaches a false gospel that cannot save (2 Corinthians 11:1-4).
To see a more detailed breakdown of this, watch our series on the topic.