In Revelation 10:7, John, tells us the mystery of God will be finished during the time of the sixth trumpet, just before the seventh trumpet sounds.
"But in the days of the voice of the seventh angel, when he shall begin to sound, the mystery of God should be finished, as he hath declared to his servants the prophets" (Revelation 10:7 KJV).
When it sounds, Christ receives the "kingdoms of this world," in Revelation 11:15. What is the mystery? It’s "Christ in you." Paul wrote, “To whom God would make known what [is] the riches of the glory of this mystery among the Gentiles; which is Christ in you, the hope of glory” (Colossians 1:27). The mystery is having Christ in His people, but it seems strange that in Revelation just before the seventh trumpet we would begin to have Jesus living in us.
Shouldn’t He be in us long before that? Of course, and He is. This is the “finishing” of the mystery. It started with us in the holy place but is completed in the most holy, the judgment at the end of the world. The completion of the mystery of God is about perfection. Colossians continues from that same verse, “that we may present every man perfect in Christ Jesus” (Colossians 1:28). The finishing of the mystery of God is Christ in His people, perfectly. These are the 144,000 who follow the Lamb wherever He goes.
Even though the finishing of the mystery of God comes just before the seventh angel sounds, there are eighteen verses between the mystery being finished and the seventh trumpet sounding. In these verses, John is telling us where we are in world history, first with the "little book" and then with the French Revolution. The "little book" was opened at the "time of the end" in 1798, at the end of the 1260 years. Inside the book, Daniel, we read about the upcoming cleansing of the sanctuary, Daniel 8:14.
Notice the context. The finishing of the mystery of God is at the time of the judgment, the end of the 2300 days. What happened on October 22, 1844? Daniel writes, “Unto two thousand and three hundred days; then shall the sanctuary be cleansed" (Daniel 8:14). Ellen White tells us this is the “foundation and central pillar of the advent faith” (Great Controversy, 409).
Moses wrote what happens on the Day of Atonement, “For on that day shall [the priest] make an atonement for you, to cleanse you, [that] ye may be clean from all your sins before the LORD...." (Leviticus 16:30). Isn’t this perfection, being clean from all our sins? Yes, “all your sins” means all, all those remaining to that time. The work of sanctification is finished; the mystery of God is finished.
The point we need to remember is that the "little book" of Revelation 10 and the French Revolution in Revelation 11, pinpoint the judgment, the time of the end and the cleansing of the sanctuary. It corresponds to the latter rain and the judgment over the mark and the seal. At this time the mystery of God will be finished, occurring just before the seventh angel sounds. Here is the seventh angel,
And the seventh angel sounded; and there were great voices in heaven, saying, the kingdoms of this world are become [the kingdoms] of our Lord, and of his Christ; and he shall reign forever and ever. Revelation 11:15
At the sounding of the seventh trumpet, the Lord finishes his mediation and changes from being a priest to becoming a king. Then He returns to this earth as King of Kings and Lord of Lords.
I have observed over the past fifty years that the teaching of the cleansing of the sanctuary has been gradually changed from the cleansing of the people of God to the cleansing of the heavenly sanctuary alone. And, total eradication of all sin has been deemphasized from before the close of probation and placed at the second coming. It’s important to note that this total cleansing comes before, not at the second coming. At the close of probation, God’s people will be free of sin, “perfect in Christ Jesus,” “Cleansed from all their sins before the Lord.” God’s people as sanctuaries will be totally cleansed before Jesus comes. Because of the “perfecting” latter rain, they will “reflect the image of Jesus fully,” (TM 506).
The new covenant promise will be complete when the judgment is complete. Ellen White in Great Controversy, 485 couples the new covenant promise with the Investigative Judgment. What is that promise? It is the completion of the mystery of God, the sealing of the 144,000 brought about by the latter rain. It’s the marking by the man with the writer’s ink horn in Ezekiel 9. Here is God’s new covenant promise:
Behold, the days come, says the LORD, that I will make a new covenant with the house of Israel, and with the house of Judah: Not according to the covenant that I made with their fathers in the day [that] I took them by the hand to bring them out of the land of Egypt; which my covenant they brake, although I was an husband unto them, says the LORD: But this [shall be] the covenant that I will make with the house of Israel; After those days, says the LORD, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people. And they shall teach no more every man his neighbor, and every man his brother, saying, Know the LORD: for they shall all know me, from the least of them unto the greatest of them, says the LORD: for I will forgive their iniquity, and I will remember their sin no more. Jeremiah 31:31-34
This is the message the Seventh-day Adventist Church has been given to share with the world. God is going to perfect His undeserving people. It’s a gift, grace through faith. In 1888 it was supposed to be the latter rain brought about by the correct understanding and proper application of justification by faith to the third angel’s message. Justification by faith is undeserved grace through faith. The third angel’s message coupled with justification by faith is the message that will perfect God’s people. Ellen white tells us:
We are in the great day of atonement, and the sacred work of Christ for the people of God that is going on at the present time in the heavenly sanctuary should be our constant study. 5T 520.
“The correct understanding of the ministration in the heavenly sanctuary is the foundation of our faith” (Letter 208, 1906; Evangelism 221). If there is only one understanding and not two or more, at least one being an incorrect understanding, then why would Ellen White use the word “correct”? This author believes there is an errant understanding that most of us are following, and that’s why we’re still here today.