The Adventist Church has a unique set of beliefs on several doctrines that set them apart from other denominations. Their theology focuses on the Hebrew Sanctuary, they keep the seventh-day Sabbath, they believe people enter an unconscious state when they die, and they highly regard a set of works called the Spirit of Prophecy. Because of these beliefs, many Christians consider Adventism a sect, even though they agree on most of the core aspects of the Christian faith, such as salvation by grace through faith and the authority of the Bible.
What Are the Origins of Adventism?

Based on his understanding of Biblical prophecy, William Miller and members of the Millerite Movement were expecting the second coming of Christ to occur in 1844. The Millerites consisted of people from different denominational affiliations, such as Baptists, the Christian Connection churches, Methodists, and Presbyterians.
When the Second Coming did not occur on October 22, 1844 (the prophecy determined by Miller’s calculations) the non-event became known as the Great Disappointment. Some Millerites abandoned their beliefs, but others believed that the prophecy of 2300 evenings and mornings, found in Daniel 8, was fulfilled. Still, they were incorrect in their belief that the event was the Second Coming.
On reinvestigating the matter, they understood it as marking an occurrence in Heaven, not on Earth. Based on their understanding of the Hebrew sanctuary system, they now believed the event marked Jesus’s entry into, and the beginning of his ministry in, the Holy of Holies. They held onto their belief in the imminent return of Christ but gradually became convinced of other unique views as well, such as the Sabbath as a day of worship instead of Sunday, which was the day of worship instituted by the Catholic Church.
Prominent leaders in the establishment and development of the Adventist Church were James White, Ellen Harmon (later White when she married James White), Joseph Bates, and J.N. Andrews.

Because of the prominence of the Sabbath and the Second Coming, the group of people who held to these beliefs called themselves Seventh-day Adventists. The Sabbath is the seventh day of the week, and Advent is a term that refers to the Second Coming. The name thus declared two of their core beliefs.
The Seventh-day Adventist Church was established in 1863 in the USA and has since developed into a global organization known for its involvement in health, education, and humanitarian work in addition to its religious activities. The headquarters of the Adventist Church is in Silver Spring, Maryland.
The Adventist Church has established several publication houses that print their materials including the Spirit of Prophecy books and the Sabbath School Quarterlies. Members study the Quarterlies which deal with a new topic every quarter. Members study the lessons daily and they are discussed on Sabbath mornings before the Divine Services during Sabbath School.
General Beliefs

Adventists believe in the Trinity, being one God consisting of three co-equal persons: the Father, the Son, and the Holy Spirit. They practice the sacraments of communion as a commemoration of the death of Christ and adult baptism. Baptism is the path to membership and follows a series of studies to ensure the baptismal candidate understands the doctrines and beliefs of the Church. However, the membership of the local church must also vote the newly baptized person into membership, which gives the new member voting rights.
Adventists believe in Sola Scriptura, Sola Gratia, and Sola Fide as all Protestant denominations do. They have a high regard for the Bible and most Adventists believe in a seven-day creation as presented in Genesis 1. They do not subscribe to the theological view that Genesis 1-11 constitutes a myth.
As the name Adventist suggests, the Second Coming is a focal point of Adventist theology. From its origins in the Millerite Movement, Adventists never lost the expectation that Jesus would return soon. This focus drives their evangelism and mission endeavors.
Distinct Beliefs

The distinct beliefs of the Seventh-day Adventist Church make up the majority of the five S’s of Adventism. These are the Sabbath, the Sanctuary, the spirit of prophecy, and the state of the dead. The only generally held “s” refers to the Second Coming.
Adventists believe the seventh-day Sabbath is the day to be observed for worship. They believe it was instituted by God at creation and cannot be changed. Adventists teach that Sunday worship, which the Catholic Church instituted, constitutes the mark of the beast when it is enforced, and they anticipate its enforcement globally. Sabbath observance, in contrast, constitutes the seal of God.
The Hebrew sanctuary system plays a significant role in Adventist theology. Since the Sanctuary presents many aspects and perspectives on the ministry of Christ, like the typology of the Lamb, the High Priest, and the Ark of the Covenant, Adventists believe the study of the Sanctuary reveals insights into the ministry of Christ in Heaven and illuminates eschatological events. Adventists believe that Satan, represented by the Azazel goat, will eventually receive the sin of humanity and will pay the ultimate price for it.
Part of the Adventist profession of faith includes accepting the spirit of prophecy. This term, which appears only in Revelation 19:10 in the Bible, refers to the writings of Elen G White who Adventists believe had the gift of prophecy. She, however, never claimed to be a prophet. She wrote a phenomenal amount of works spanning a wide range of topics from commentary on the Biblical narrative to health, wellness, leadership, devotional life, Christian living, and much more.

Seventh-day Adventists also have a unique view of the state of the dead. They believe in conditional immortality and reject the idea of an inherent immortal soul. When a person dies, they go into an unconscious state sometimes referred to as “soul sleep.” At the Second Coming, the believers who have passed are awoken and resurrected with immortal bodies, having no conscious knowledge of anything that occurred between death and having been raised.
Adventists differ from other Protestant denominations in their belief that the Ten Commandments are still binding on believers today. They are often erroneously accused of believing that observance of the commandments leads to salvation. They do not believe in salvation by works. Salvation by grace through faith is a core tenet of Adventism. They argue that other Protestant denominations would accept the Ten Commandments as binding were it not for the fourth commandment: Keep the Sabbath. They believe the observance of the Ten Commandments is a result of having been saved, highlighting the introduction to the commandments in Exodus 20: “I am the LORD your God, who brought you out of the land of Egypt, out of the house of slavery.” God declared that he saved them, and then gave the commandments as the expected standard to live by now that they have been saved.
Structure

There are approximately 22 million Adventists worldwide, with almost one-third residing in Africa. The Seventh-day Adventist Church has a hierarchical structure that sees churches and companies fall under a Conference according to geographical location. Conferences employ pastors who are assigned a church or churches to care for and minister to. The conference has an executive committee consisting of members elected from the local churches as well as some pastors who meet to discuss and approve matters relevant to that conference. Every four years a conference calls a session where the officers of the Conference are elected.
Several Conferences fall under a Union. A Union is the only church structure in Adventism that may ordain pastors and approve applications for marriage licenses. Unions coordinate evangelism, ministry, training, and other events that are broader than the area a Conference manages.

Several Unions fall under a structure called a Division. The world has been divided into 13 Divisions and each division is part of the General Conference, which is the highest structure in Adventism. Each Division has an elected president who also serves as a vice-president of the General Conference. The 13 Divisions are the East Central African Division, the Euro-Asia Division, the Inter-American Division, the Inter-European Division, the North American Division, the Northern Asia-Pacific Division, the South American Division, the South Pacific Division, the Southern African Indian Ocean Division, the Southern Asia Division, the Southern Asia-Pacific Division, the Trans European Division, and the West-Central Africa Division.
Once every five years, representatives from each Conference, Union, and Division gather at the General Conference where the leaders for the next five years are elected and issues about the global church are discussed.
The Adventist Church has the second-largest school and hospital system in the world. In both instances, the Catholic Church has the largest number. These establishments highlight the Adventist Church’s commitment to education and health.