Explore the profound experience of the Great Disappointment on October 22, 1844, foretold in Revelation 10’s prophecy of the “bitter” little book. Understand that while the Millerites correctly calculated the time of the 2300-day prophecy’s end, they misunderstood the event, expecting Christ’s return instead of the start of the sanctuary’s cleansing in heaven. Witness God’s immediate comfort and guidance through Hiram Edson’s vision the very next morning, revealing Christ’s movement into the Most Holy Place of the heavenly sanctuary to begin the Investigative Judgment. Recognize this pivotal moment as the fulfillment of Revelation 11:19 and the foundation for understanding the Third Angel’s Message.