In Seventh-day Adventist theology, the heavenly sanctuary teaching asserts that many aspects of the Hebrew tabernacle or sanctuary are representative of heavenly realities. In particular, Jesus is regarded as the High Priest who provides cleansing for human sins by the sacrificial shedding of his blood. The doctrine grew out of the church's interpretation of the 1844 Great Disappointment. As a whole, it is unique to Seventh-day Adventism, although other Christians share many of the typological identifications made by the epistle to the Hebrews. One major aspect which is completely unique to Adventism is that the day of atonement is a type or foreshadowing of the investigative judgment. Technically, the "heavenly sanctuary" is an umbrella term which includes the investigative judgment, Christ's ministry in heaven before then, the understanding of , etc. However, it is often spoken of interchangeably with the investigative judgment.
The earthly Most Holy Place was entered once a year by the High Priest on the Day of Atonement to offer atonement for the Israelites. Adventists believe this is a "type" of Jesus' ministry in heaven. In 1844 Jesus moved from the Holy Place of the heavenly sanctuary into the Holy of Holies to begin a final atonement for humanity. This is understood as a change in two phases of Jesus' ministry.
One of the church's official 28 fundamental beliefs is:
The historical foundation of the doctrine began with the Millerites who expected Jesus to return to earth on October 22, 1844. They interpreted the cleansing of the sanctuary () to mean the cleansing of the earth by Jesus' coming. After the "Great Disappointment" when Christ did not come, those who awaited Christ further studied the prophecies and reached the understanding that the event reached in time prophecy was actually the cleansing of the heavenly sanctuary. This understanding then initiated the Seventh-day Adventist Church.