The claim to uniqueness in the title of this essay can be seen to rest on firm foundations, of which we examine these three: first and foremost its [Baha’u’llah’s Covenant] written, explicit, indisputable statement in the Hand of its Author for all to see; second, its evident and most-prominent place in a series of Covenants that have brought the Revelations of the Báb and Bahá’u’lláh unmarred, whole, and vital, into the hands of the world’s peoples; and third, the utterly-diverging fates of those who either embraced or rejected it.
Regarding the first of these identified foundations, Shoghi Effendi writes:
‘… this unique and epoch-making Document, designated by Bahá’u’lláh as His “Most Great Tablet,” and alluded to by Him as the “Crimson Book” in His “Epistle to the Son of the Wolf,” can find no parallel in the Scriptures of any previous Dispensation, not excluding that of the Báb Himself. For nowhere in the books pertaining to any of the world’s religious systems, not even among the writings of the Author of the Bábí Revelation, do we find any single document establishing a Covenant endowed with an authority comparable to the Covenant which Bahá’u’lláh had Himself instituted.
‘“So firm and mighty is this Covenant,” He Who is its appointed Center [‘Abdu’l-Bahá] has affirmed, “that from the beginning of time until the present day no religious Dispensation hath produced its like.” “It is indubitably clear,” He, furthermore, has stated, “that the pivot of the oneness of mankind is nothing else but the power of the Covenant.”’
Also from Shoghi Effendi:
“This Primitive Age of the Bahá’í Era, unapproached in spiritual fecundity by any period associated with the mission of the Founder of any previous Dispensation, was impregnated, from its inception to its termination, with the creative energies generated through the advent of two independent Manifestations and the establishment of a Covenant unique in the spiritual annals of mankind.”
The unique character of the Covenant of Bahá’u’lláh, as expressed in His Kitáb-i-‘Ahd (Book of the Covenant) and Hid Kitáb-i-Áqdas (The Most Holy Book, the book of the laws of His Dispensation), emerges first in His explicit, written assertions in these two revealed works, assertions in a form unprecedented in all of recorded human history. In the words of the distinguished historian and scholar Adib Taherzadeh:
“Through these writings Bahá’u’lláh established a mighty and irrefutable covenant unprecedented in the annals of past religions. Never before has a Manifestation of God left behind an authoritative statement in which He has explicitly directed His people to turn to someone as His successor, or follow a defined system of administration for governing the religious affairs of the community.”
Regarding the second of the foundations of the claim to this Covenant’s uniqueness, one need only contemplate its place in the series of clear transfers of authority that began with the Báb and led onward through Bahá’u’lláh, ‘Abdu’l-Bahá, Shoghi Effendi, and the Universal House of Justice, all in their ushering in of the great Bahá’í cycle of future Dispensations. This series can be viewed as the living realization of “the cord to which have clung all in this world and in the world to come”, as one reads in Bahá’u’lláh’s prayer to be recited during the Bahá’í Fast. The essays comprising the series of which the present essay is but one part, provide a broad survey of this theme, one which requires entire volumes for the beginnings of an adequate treatment. It should be sufficient here to note that in no other faith has such a cord of connection ever been explicitly furnished to the followers of God.
Regarding the third of the foundations of the claim, one is reminded of the challenge appearing in Bahá’u’lláh’s great Tablet of Ahmad, “Whosoever desireth, let him turn aside from this counsel, and whosoever desireth, let him choose the path to his Lord.”
The uniqueness of this Covenant, termed the “Lesser Covenant” to distinguish it from the overarching Covenant of God with all of humanity for all of His Dispensations, is demonstrated most clearly through its continuing shielding of the Bahá’í Community from schism, deformity, and confusion. The choice of devotion or infidelity stands always before each of us. In His Tablet of Visitation, Bahá’u’lláh testifies to this divergence:
“I bear witness… that through a word from Thee Thou hast decided between all created things, causing them who are devoted to Thee to ascend unto the summit of glory, and the infidels to fall into the lowest abyss.”
In a Tablet to Howard MacNutt, ‘Abdu’l-Bahá wrote:
“Today, every wise, vigilant and foresighted person is awakened, and to him are unveiled the mysteries of the future which show that nothing save the power of the Covenant is able to stir and move the heart of humanity, just as the New and Old Testaments propounded throughout all regions the Cause of Christ and were the pulsating power in the body of the human world. A tree that hath a root shall bear fruit, while the tree that hath none, no matter how high and hardy it may be, will eventually wither, perish and become but a log fit for the fire.
“The Covenant of God is like unto a vast and fathomless ocean. A billow shall rise and surge therefrom and shall cast ashore all accumulated foam.”
And so it was when the Bahá’í community was assailed by those who disputed the authority conferred on ‘Abdu’l-Bahá the Center of Bahá’u’lláh’s Covenant. No proof of the Covenant’s power is clearer than the sobering fates that befell those who attacked it, in stark contrast to the steadily-emerging splendor of the globe-girdling development of the Bahá’í community continuing today – the very community the attackers sought to seize for their very own.
For one mighty example of what befell the breakers of Bahá’u’lláh’s Covenant, we turn to Shoghi Effendi once more, as he writes of ‘Abdu’l-Bahá’s half-brother, Mirzá Muhammad-‘Alí and those who took his side against the Master:
“And finally, he who, from the moment the Divine Covenant was born until the end of his life, showed a hatred more unrelenting than that which animated the afore-mentioned adversaries of ‘Abdu’l‑Bahá, who plotted more energetically than any one of them against Him, and afflicted his Father’s Faith with a shame more grievous than any which its external enemies had inflicted upon it—such a man, together with the infamous crew of Covenant-breakers whom he had misled and instigated, was condemned to witness, in a growing measure, as had been the case with Mírzá Yaḥyá and his henchmen, the frustration of his evil designs, the evaporation of all his hopes, the exposition of his true motives and the complete extinction of his erstwhile honor and glory. His brother, Mírzá Ḍíyá’u’lláh, died prematurely; Mírzá Áqá Ján, his dupe, followed that same brother, three years later, to the grave; and Mírzá Badí‘u’lláh, his chief accomplice, betrayed his cause, published a signed denunciation of his evil acts, but rejoined him again, only to be alienated from him in consequence of the scandalous behavior of his own daughter. Mírzá Muḥammad-‘Alí’s half-sister, Furúghíyyih, died of cancer, whilst her husband, Siyyid ‘Alí, passed away from a heart attack before his sons could reach him, the eldest being subsequently stricken in the prime of life, by the same malady. Muḥammad-Javád-i-Qazvíní, a notorious Covenant-breaker, perished miserably. Shu‘á‘u’lláh who, as witnessed by ‘Abdu’l‑Bahá in His Will, had counted on the murder of the Center of the Covenant, and who had been despatched to the United States by his father to join forces with Ibráhím Khayru’lláh, returned crestfallen and empty-handed from his inglorious mission. Jamál-i-Burújirdí, Mírzá Muḥammad-‘Alí’s ablest lieutenant in Persia, fell a prey to a fatal and loathsome disease…”
Contrast these sordid outcomes and others in the remainder of this sobering passage with the steadily-unfolding advancement of the Cause of God, alive, thriving, and animating human advancement in the world today, and we see an irrefutable, visible proof of the uniqueness of the Covenant of Bahá’u’lláh. This “vast and fathomless ocean” firmly casts ashore all its “accumulated foam”.
The clear, explicit, written character of Bahá’u’lláh’s Covenant; its pivotal, enduring, and essential place in the stream of a cycle destined to span half a million years of continuing Revelations in the future; and the irresistible potency of its protection of those who enter unshakably into its embrace: all these testify to its utter uniqueness among the Revelations lavished by God on humanity. Thanks to the bestowal of this Covenant of Bahá’u’lláh, we stand near the very beginnings of a golden era of astonishment, wonder, and splendor.
 God Passes By
Author: Shoghi Effendi Source: US Bahá’í Publishing Trust, 1979 second printing Pages: 412
 Citadel of Faith pp. 4-6
 Adib Taherzadeh, The Covenant of Baha’u’llah, p. 99
 Selections From the Writings of ‘Abdu’l-Bahá
Author: ‘Abdu’l-Bahá Source: Bahá’í World Centre, 1982 lightweight edition Pages: 320
 Shoghi Effendi, God Passes By, pp. 316-320