The World Order of Bahá'u'lláh is a collection of letters and messages from Shoghi Effendi, head of the Bahá'í Faith during the period, first published in 1938.
While the letters to the American Bahá'í community from Shoghi Effendi between 1922 and 1929, published under the title of Bahá'í Administration, explained and encouraged the development of the administrative institutions created by Bahá'u'lláh and further elaborated by `Abdu'l-Bahá, the letters published in The World Order of Bahá'u'lláh have a different aim and a far larger scope. These later communications unfold a clear vision of the relation between the Bahá'í community and the entire process of social evolution under the dispensation of Bahá'u'lláh. The distinction between the Bahá'í community and the sects and congregations of former religions had been made apparent, but the present volume establishes the Baha'i Administrative Order as the nucleus and pattern of the world civilization emerging.
In light of the existing international chaos, they reveal the most significant Truth of this era, namely that the old conception of religion, which separated spirituality from the fundamental functions of civilization, compelling men to abide by conflicting principles of faith, of politics and of economics, has been forever destroyed.
In the section entitled "Unity in Diversity", Shoghi Effendi described underlying principles of the Baha'i Faith,
Let there be no misgivings as to the animating purpose of the world-wide Law of Bahá'u'lláh. Far from aiming at the subversion of the existing foundations of society, it seeks to broaden its basis, to remold its institutions in a manner consonant with the needs of an ever-changing world. It can conflict with no legitimate allegiances, nor can it undermine essential loyalties. Its purpose is neither to stifle the flame of a sane and intelligent patriotism in men's hearts, nor to abolish the system of national autonomy so essential if the evils of excessive centralization are to be avoided. It does not ignore, nor does it attempt to suppress, the diversity of ethnical origins, of climate, of history, of language and tradition, of thought and habit, that differentiate the peoples and nations of the world. It calls for a wider loyalty, for a larger aspiration than any that has animated the human race. It insists upon the subordination of national impulses and interests to the imperative claims of a unified world. It repudiates excessive centralization on one hand, and disclaims all attempts at uniformity on the other. Its watchword is unity in diversity...(Effendi 1938:41-42).