There is no religion or cult, no matter how incredible, that has not attracted a community of believers. As long as a religion or cult stipulates supernatural beings or powers (for the existence of which there is not a shred of evidence) and imposes commandments (no matter how absurd) -- in other words, as long as the religion or the cult provides its followers with something to believe in and obey besides themselves -- there will be devotees 
he following is a selection of examples of such unreasonable beliefs. In each case we shall identify the gullible suckers who believed (or still believe) and were (or still are) willing to live (or die) for their beliefs. 
          If you are a religious person, in reading this you should note that all the beliefs seem ridiculous, with the sole exception of the one you happen to believe in. 

John Frum is a divine being in the shape of an American World War II serviceman. If the believers build mockups of airstrips and imitate the actions of the American soldiers stationed on the island during the war (1942-5) John Frum will return with airplanes loaded with modern manufactured goods, bringing wealth and prosperity.
(followers of the Cargo Cult on the island of Tanna in Vanuatu) 

Prince Philip (1921-) the Duke of Edinburgh, the husband of Queen Elizabeth II of England, is a divine being, the pale-skinned son of a mountain spirit and the brother of John Frum. He traveled to a distant land and married a powerful woman, but he will return.
(the Yaohnanen tribe on the island of Tanna in Vanuatu) 

The god Shiva asked his consort Devi Durga to correct the imbalance between creation and destruction. In the 14th century she created a band of ferocious men and ordered them to commit ritual assassinations, promising them immunity from punishment.
(members of Thugee or Thugs) 

In the science fiction novel Stranger in a Strange Land by Robert A. Heinlein (1961) the hero is a human raised by Martians on Mars. When he returns to earth he is shocked by the inferiority of human society. He founds an interplanetary church which uses Martian wisdom to ameliorate human suffering. The task of believers is to do the same thing in real life.
(members of the Church of All Worlds) 

Lindberg Sanders (1934-1983) was the Black Jesus. He forbade his followers to eat pork or to drink water, and warned them that the next lunar eclipse would herald the end of the world. They barricaded themselves in their house in Memphis, Tennessee, took a policeman hostage, and tortured and killed him. In the ensuing gun battle with the police, all were killed.
6 followers of Lindberg Sanders) 

Roch Theriault (1947- ) is the reincarnation of Moses. In 1977 he convinced his followers to sell all their belongings, sever ties with their families, and live in a commune under his leadership. He used all the women as his wives, mutilated several members, circumcised some, and tried to perform healing miracles on others causing their deaths. Even after he was imprisoned for murder in 1993, three wives paid him conjugal visits and bore him children.
(38 followers of Roch Theriault) 

Marshall Applewhite (1931-1997) arrived on earth via UFO from another dimension, and he taught his followers how to accompany him on the return journey. When comet Hale-Bopp appeared in 1997 he said that the earth was about to be recycled, and the members must commit suicide so that their souls would be transferred to the spaceship hiding behind the comet. They all committed suicide together.
(39 members of Heaven's Gate) 

Fred W. Phelps (1929- ), a disbarred lawyer, is the only righteous man on earth, and his followers are his slaves. God hates: homosexuals, Jews, Roman Catholics, Muslims, America, etc. (the list is endless). Members of his church picket the funerals of American soldiers killed in action, claiming that their deaths are God's punishment for America's toleration of homosexuals.
(71 members of Westboro Baptist Church, of whom 60 are Phelps's family) 

Jehovah Wanyonyi (1924?-) is God, the father of Jesus Christ. He created Adam and Eve, and spoke to humanity through Jesus until Jesus went to heaven. Wanyonyi is also able to cure AIDS. He lives in western Kenya with 25 wives and their 95 children.
(120 Lost Israelites) 

Jim Jones (1931-1978) was an incarnation of Jesus, Akhenaten, Buddha, Lenin, and Father Divine, who performed healing miracles. In 1977 he moved with his followers to an isolated community called Jonestown. In 1978 a delegation came to investigate allegations of cruelty and abuse. Members of the community killed some of the delegates and several deserters from the cult, and then almost all the members of the community murdered each other and/or committed suicide.
(1000 members of the People's Temple) 

Juhaiman ibn Muhammad ibn Saif al Utaibi (1936-1980) was a militant whose son-in-law was the Mahdi (Messiah). Al-Utaibi preached fundamentalist puritanical xenophobic Islam, even rejecting the government of Saudi Arabia as corrupt and servile to the West. In 1979 he led his private army to seize the Grand Mosque in Mecca, where they held out for several weeks.
(1300 followers of Juhayman ibn Muhammad ibn Sayf al-Utaibi) 

Rabbi Nachman (1772-1810) combined Hasidism with esoteric Kabbala. After his death his followers continue to see him as their leader, and they make annual pilgrimages to his grave in the Ukraine.
(20,000 Breslav Hasidim) 

Shoko Asahara (1955- ) taught Buddhist asceticism combined with modern technology. His followers learned cessation of oxygen consumption, reduction of heart activity, and changing of electromagnetic brain activity. They stockpiled sarin nerve gas, and in 1995 released the gas in the Tokyo subway, killing and injuring about 5000 people.
(40,000 members of Aum Shinnikyo).

The peasant Daniil Filippovich (17th century) was an incarnation of God, and founded a religion in which the believers attained divine grace by ecstatic rituals, including flagellation and sexual orgies.
(40,000 Khlysts) 

Ludvic Lazarus Zamenhof, (1859-1917), the inventor of the artificial international language Esperanto, is a supernatural spirit to be worshipped.
(45,000 followers of Oomoto) 

In 1973, Claude Vorilhon (1946- ) met an extraterrestrial alien who had landed on earth. The alien's message for humanity was, that advanced scientists from another planet had created all life on earth, and men must prepare for their return. Meanwhile mankind must learn new meanings of all the scriptures of all religions, and also cloning of humans, mind transfer, and total sexual freedom.
(65,000 Raelians)

The chief deity is a mighty great rabbit called Menabosho or Michabo. After death, humans go to join this deity.

(70,000 Algonquin Indians) 

Kanichi Otsuka (1891- ) is God, who assumed human form in 1947 in order to found his religion. Believers must reject science and reason and serve his plan to exterminate all peoples except the Japanese. The founder has been convicted on charges of child molestation and rape.
(100,000 members of Shinreikyo) 

Sabbatai Zevi (1626-1676) declared himself to be the long-awaited Messiah. Many Jews received him with enthusiasm. But when he was arrested by the Turks in 1666 he saved his skin by converting to Islam, causing devastating disillusionment among his followers. Yet even today there are those who worship him as God's anointed saviour.
(100,000 Sabbateans) 

Ahura Mazda is the one God and Zoroaster (9th/10th century) is his prophet. Mazda created only order, but there is also chaos, and all living things are responsible for the outcome of the struggle between the two.
(200,000 Zoroastrians) 

In the Dreamtime, the ancestral spirits sang the rocks, plants, and animals into existence.
(200,000 Australian Aborigines) 

In 1935, Jesus appeared to Sun Myung Moon (1920-2012) and asked him to continue His work, which was interrupted by the crucifixion. Later, Moon also conversed with Moses and Buddha. Any follower of Moon can be resurrected through obedience to his church. Accusations proven against his church include: brainwashing, child abuse, financial crimes, anti-semitism, mass forced marriages, and planning a world dictatorship with Moon as dictator.

(250,000 members of the Unification Church or "Moonies") 

Humans are immortal spiritual beings called thetans, who have a long history in this universe going back over innumerable lifetimes. The pseudo-scientific book Dianetics: The Modern Science of Mental Health (1950) by the founder of the church, Lafayette Ronald Hubbard (1911-1986) is the only source of truth, and any alteration of the techniques as he defined them is a high crime.
(500,000 Scientologists) 

Haile Selassie (1892-1975), the former Emperor of Ethiopia, was God incarnate. His supposed death was a hoax. He will return and liberate his followers.
(600,000 Rastafarians) 

Al-Hakim bi-Amr Allah, the sixth Fatimid Caliph who ruled in Egypt (996-1021) was an incarnation of God. He did not really die, but was hidden by God and will return as the Mahdi (Messiah) on judgement day.
(1 million Druze) 

Tenzin Gyatso (1935- ), the Dalai Lama and the spiritual ruler of Tibet, is the reincarnation of the bodhisattva of compassion. When he dies, his monks will search until they identify a small child as his reincarnation, and they will bring the child to Lhasa to train him for his role.
(2 million Tibetans) 

Everything in the world contains a spiritual essence. Any action or omission of action that is defined as "dirtiness" requires a purification ritual to placate the spirits.
(4 million Shintoists) 

A universal God has expressed His will through a succession of divine messengers who founded different religions. Bahaullah (1817-1892) fulfilled the messianic expectations of all previous religions.
(6 million Bahai) 

Sathya Sai Baba (1926- ) is an incarnation of Shiva sent to earth to bring about spiritual renewal. He cures the sick, causes objects to materialize, levitates, and performs other miracles.
(6 million followers of Sathya Sai Baba) 

The one and only God who created the world decided that the Israelites are His chosen people. God gave them the law, which imposes on them 613 commandments. Men must never be bareheaded, under any circumstances.

(14 million Jews) 

Immortal spirits perfect themselves by constant reincarnation. Spirits can communicate with living people through mediums, and interfere in their lives. Many planets in the universe are inhabited.
(15 million Spiritists) 

The gods sacrificed themselves so that mankind could live. The world consists of the corpses of the sacrificed gods. Mankind repays its debt to the gods by sacrificing the gods.
(25 million Aztecs) 

The purpose of human life is to achieve union with the universal god. The obstacles to this are worldly pursuits which condemn humans to an endless cycle of reincarnations. All men (and some women) must wear a turban at all times, under any circumstances.
(26 million Sikhs) 

The spirit of every person is part of Brahman, the supreme spirit, which appears in many godlike incarnations. The purpose of human life is to realize one's identity with the supreme spirit.
(900 million Hindus) 

God revealed to his prophet Mohammed (ca 570-632) the Koran, a holy book which contains the only truth. Believers must pray five times a day, at least once in their lives make a pilgrimage to Mecca, and wage holy war against unbelievers. It is forbidden to pray in a mosque while wearing shoes.
(1.2 billion Muslims) 

The Eucharist is not merely a wafer and wine, but the actual body and blood of Christ.
(1.2 billion Roman Catholics and Eastern Orthodox Christians) 

Jesus of Nazareth, the son of God, was crucified like a criminal, thereby saving all of humanity from eternal punishment for the sin committed by Adam and Eve in the Garden of Eden. It is forbidden to pray in a church while wearing a hat.
(2.1 billion Christians)