The unity of all religions

Baha'is affirm the essential unity of all the great religions, that the world's major faiths spring from one God and form successive chapters of a single, unfolding revelation. On this teaching of progressive revelation, God has sent a series of Messengers (among them Abraham, Moses, Krishna, the Buddha, Zoroaster, Jesus, Muhammad, the Bab, and Baha'u'llah), each renewing the eternal truths and advancing them to meet the needs of a new age. The differences among religions are attributed to the varying times, places, and capacities they addressed, while their spiritual core is held to be one.

Baha'u'llah set out the doctrine at length in the Kitab-i-Iqan (Book of Certitude, 1862), arguing from the Bible and the Quran that each of God's Messengers, termed Manifestations of God, has been rejected in his own time by the very religious authorities who claimed to await him, a pattern the book reads as continuing in the response to the Bab and to Baha'u'llah himself. The claim is not accepted by the religions it names as predecessors: mainstream Sunni and Shia Islam holds Muhammad the final prophet and treats any claim to further prophecy as incompatible with that finality, a position that has led some Muslim-majority states to treat the Baha'i Faith as heretical rather than as a legitimate independent religion, and Christian orthodoxy similarly holds the revelation in Christ complete rather than awaiting a further Messenger.

This affirmation is a central and defining principle of the Baha'i Faith, founded in nineteenth-century Persia, and it stands alongside the twin teachings of the oneness of God and the oneness of humanity. From it flow the tradition's emphases on the elimination of prejudice, the harmony of religion and reason, and the goal of world unity. The Baha'i view distinguishes it from the exclusive truth-claims some traditions make for themselves, since it regards each as a genuine, time-bound expression of one religion of God, while itself claiming to be the revelation appointed for the present age.

The Bab, Baha'u'llah's forerunner, was executed by firing squad in Tabriz in 1850, and Baha'u'llah himself declared his own mission in the Garden of Ridvan outside Baghdad in 1863, events the faith reads as confirming the pattern of rejection its doctrine of unity predicts. Because the exclusivist claims of the older religions persist, Baha'is in Iran, the faith's birthplace, have faced sustained state persecution since the nineteenth century, including, since the 1979 revolution, exclusion from universities and confiscation of property, treatment the Iranian state justifies by denying the Baha'i Faith is a genuine religion at all. Baha'i teaching holds that a new Manifestation appears roughly every thousand years or whenever humanity's capacity requires it, though the precise interval is not fixed doctrine.