For the Christian belief see Progressive revelation (Christian)
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Symbols · Laws Teachings · Literature Calendar · Divisions Pilgrimage Progressive revelation is a core teaching in the Bahá'í Faith that suggests that religious truth is revealed by God progressively and cyclically over time through a series of divine Messengers,

Progressive cycles
Bahá'ís believe God to be generally regular and periodic in revealing His will to mankind through messengers/prophets. Each messenger in turn establishes a covenant and founds a religion. This process of revelation is also never ceasing, according to the Bahá'í writings, contrary to many other belief systems that believe in a finality of their prophet/messenger. Muhammad, Jesus, Buddha, Moses, Zoroaster, and Krishna were all named by Bahá'u'lláh as being among these establishers of religion, termed Manifestations of God, as well as himself, and his forerunner the Báb. Bahá'u'lláh also expressly or implicitly referred to Adam, Noah, Saleh, Húd, and an unnamed prophet of the Sabians as messengers of God.
The general theme of the successive and continuous religions founded by Manifestations of God is that there is an evolutionary tendency, and that each Manifestation of God brings a larger measure of revelation (or religion) to humankind than the previous one.

Dispensations
In addition to the idea of religion being progressively revealed from the same God through different prophets/messengers, there also exists in Bahá'í literature, the idea of a universal cycle,

Metaphors
The earliest forms of religion are seen, in many of the Bahá'í Writings, to be like early school. Concepts which may have been appropriate at an earlier time, then, might be quite inaccurate when one has sufficient context. Bahá'ís would not say that these earlier beliefs were wrong, since they were sufficient to the capacity of humanity at the time.
These views allow Bahá'ís to resolve many of the apparent conflicts between the differing theologies and cosmologies of the world. Each different religion may have had truth explained differently according to the needs of the recipients of the teaching. Bahá'u'lláh was asked several questions about the nature of differences in religions, God's messengers, and religious laws. His response was a reference to progressive revelation:
The All-Knowing Physician hath His finger on the pulse of mankind. He perceiveth the disease, and prescribeth, in His unerring wisdom, the remedy. Every age hath its own problem, and every soul its particular aspiration. The remedy the world needeth in its present-day afflictions can never be the same as that which a subsequent age may require. Be anxiously concerned with the needs of the age ye live in, and centre your deliberations on its exigencies and requirements.

Religion as a school
One key purpose of religion, says Bahá'u'lláh, is to "carry forward an ever advancing civilisation...".[2] He elsewhere says:
"O ye children of men! The fundamental purpose animating the Faith of God and His Religion is to safeguard the interests and promote the unity of the human race, and to foster the spirit of love and fellowship amongst men. Suffer it not to become a source of dissension and discord, of hate and enmity. This is the straight Path, the fixed and immovable foundation. Whatsoever is raised on this foundation, the changes and chances of the world can never impair its strength, nor will the revolution of countless centuries undermine its structure. Our hope is that the world's religious leaders and the rulers thereof will unitedly arise for the reformation of this age and the rehabilitation of its fortunes. Let them, after meditating on its needs, take counsel together and, through anxious and full deliberation, administer to a diseased and sorely-afflicted world the remedy it requireth."

Bahá'u'lláh, Gleanings from the Writings of Bahá'u'lláh, p. 215. [3]

Religion's social and educational effect
Bahá'ís believe that religious teachings are of two varieties: essential spiritual truth, and ephemeral social constructs. The latter may include laws of conduct, diet, institutions, ceremonies, etc. These may change dramatically from Manifestation to Manifestation. The former, however, are essential and do not change, except perhaps in their cultural presentation.
A good example of this is the prohibition on the consumption of cloven-hooved animals in Judaism, which is seen by Bahá'ís as a sound teaching necessary for public health at the time. Modern hygiene and medical knowledge has given us better abilities to ward off the parasites and other harmful aspects of such consumption, and so such restrictions are not part of the Bahá'í Faith.
So the Manifestation of God is seen as at once restoring the essential truth, returning the faithful to the correct practice. Simultaneously, the Manifestation eliminates redundant or corrupt social structures and creates such social organization as will support the improvement of mankind.
Bahá'ís see Bahá'u'lláh as the most recent teacher, the most recent Manifestation.

Religious truth is of two kinds
Bahá'ís accept the founders of the "major world religions" as Manifestations of God, as well as some who are not well known, or whose religions have all but disappeared. The usual list Bahá'ís commonly refer to include: Krishna, Buddha, Zoroaster (Zarathustra), Abraham, Moses, Christ, Muhammad, the Báb, and Bahá'u'lláh. Others are referred to in Bahá'í Writings or confirmed from Islamic and other sources, including Joseph, Noah, Hud, Salih, and the founder of the "religions of the Sabeans", a religion which, according to Shoghi Effendi, was widespread in Chaldea at the time of Abraham.
Furthermore, the existence of unnumbered previous religions of which we have no modern knowledge is confirmed by the Guardian:
"These religions are not the only true religions that have appeared in the world, but are the only ones still existing. There have always been divine Prophets and Messengers, to many of whom the Qur'án refers. But the only ones existing are those mentioned above."

Shoghi Effendi, quoted in the compilation Lights of Guidance, p. 414.
Additionally, Bahá'ís are taught that some worthy religions are not revealed by Manifestations of God. These were founded by spiritual leaders who were members of the great faiths and were religious teachers "sensitive to the spiritual currents flowing" at the time of the appearance of a new Manifestation of God. These religions, while not authoritative, are nevertheless a reflection of divine teachings and are treated with respect.
Finally, Bahá'í teachings allow for the existence of dangerous and destructive religions groups which are either distortions of true faith, or "the outcome of human perversity." The Bahá'í sacred writings and Bahá'í leadership makes no attempt to explicitly identify these, though the common understanding is that this refers to personality cults, political hijacking or subversion of legitimate religions, or money scams and the like.
With the exception of the above mentions, the Bahá'í Faith tends to stay aloof from discussions of which faith or denomination is legitimate or "closer to the truth". Given that they see Bahá'u'lláh as having offered the most recent revelation from God to mankind, such distinctions are seen as somewhat redundant, and ultimately unhelpful to the goal of uniting humanity.

Types of religions and religious founders

Establishing texts
Bahá'u'lláh's seminal Kitáb-i-Íqán (in English, The Book of Certitude) is probably the best original description of the Bahá'í view of Progressive Revelation. In it Bahá'u'lláh describes the relationships between several Abrahamic prophets and how each accepted the previous, but was rejected by the previous prophet's followers. He uses these examples to highlight the legitimacy of the Báb to the reader, since the book was written in answer to some questions from the Báb's uncle. The work, however, establishes this core doctrine of the Bahá'í Faith and is seen as being of more general applicability.

'Kitáb-i-Íqán' ('The Book of Certitude')
A variety of Bahá'u'lláh's letters to rulers and religious leaders of the day, as well as some general epistles are collected in the book Summons of the Lord of Hosts. Several of the declarations include exhortations to lay down arms, conflicts, and divisions and to promote unity. In particular, religious prejudice is targeted in various places as being, not only a cause of disunity, but unjustified in fact.

See also