The fundamental principle enunciated by Bahá'u'lláh ... is that religious truth is not absolute but relative, that Divine Revelation is a continuous and progressive process, that all the great religions of the world are divine in origin, that their basic principles are in complete harmony, that their aims and purposes are one and the same, that their teachings are but facets of one truth, that their functions are complementary, that they differ only in the nonessential aspects of their doctrines, and that their missions represent successive stages in the spiritual evolution of human society....
...His mission is to proclaim that the ages of the infancy and of the childhood of the human race are past, that the convulsions associated with the present stage of its adolescence are slowly and painfully preparing it to attain the stage of manhood, and are heralding the approach of that Age of Ages when swords will be beaten into plowshares, when the Kingdom promised by Jesus Christ will have been established, and the peace of the planet definitely and permanently ensured. Nor does Bahá'u'lláh claim finality for His own Revelation, but rather stipulates that a fuller measure of the truth He has been commissioned by the Almighty to vouchsafe to humanity, at so critical a juncture in its fortunes, must needs be disclosed at future stages in the constant and limitless evolution of mankind.
The Bahá'í Faith upholds the unity of God, recognizes the unity of His Prophets, and inculcates the principle of the oneness and wholeness of the entire human race. It proclaims the necessity and the inevitability of the unification of mankind, asserts that it is gradually approaching, and claims that nothing short of the transmuting spirit of God, working through His chosen Mouthpiece in this day, can ultimately succeed in bringing it about. It, moreover, enjoins upon its followers the primary duty of an unfettered search after truth, condemns all manner of prejudice and superstition, declares the purpose of religion to be the promotion of amity and concord, proclaims its essential harmony with science, and recognizes it as the foremost agency for the pacification and the orderly progress of human society....
Mírzá Husayn-'Ali, surnamed Bahá'u'lláh (the Glory of God), a native of Mazindaran, Whose advent the Báb [Herald and Forerunner of Bahá'u'lláh] had foretold, ... was imprisoned in Tihrán, was banished, in 1852, from His native land to Baghdád, and thence to Constantinople and Adrianople, and finally to the prison city of `Akká, where He remained incarcerated for no less than twenty-four years, and in whose neighborhood He passed away in 1892. In the course of His banishment, and particularly in Adrianople and `Akká, He formulated the laws and ordinances of His Dispensation, expounded, in over a hundred volumes, the principles of His Faith, proclaimed His Message to the kings and rulers of both the East and the West, both Christian and Muslim, addressed the Pope, the Caliph of Islam, the Chief Magistrates of the Republics of the American continent, the entire Christian sacerdotal order, the leaders of Shi'ih and Sunni Islam, and the high priests of the Zoroastrian religion. In these writings He proclaimed His Revelation, summoned those whom He addressed to heed His call and espouse His Faith, warned them of the consequences of their refusal, and denounced, in some cases, their arrogance and tyranny....
The Faith which this order serves, safeguards and promotes is ... essentially supernatural, supranational, entirely non-political, non-partisan, and diametrically opposed to any policy or school of thought that seeks to exalt any particular race, class or nation. It is free from any form of ecclesiasticism, has neither priesthood nor rituals, and is supported exclusively by voluntary contributions made by its avowed adherents. Though loyal to their respective governments, though imbued with the love of their own country, and anxious to promote at all times, its best interests, the followers of the Bahá'í Faith, nevertheless, viewing mankind as one entity, and profoundly attached to its vital interests, will not hesitate to subordinate every particular interest, be it personal, regional or national, to the over-riding interests of the generality of mankind, knowing full well that in a world of interdependent peoples and nations the advantage of the part is best to be reached by the advantage of the whole, and that no lasting result can be achieved by any of the component parts if the general interests of the entity itself are neglected....
--Shoghi Effendi