Covenant of God

From the Writings of Baha'u'llah:
The first duty prescribed by God for His servants is the recognition of Him Who is the Dayspring of His Revelation and the Fountain of His laws, Who representeth the Godhead in both the Kingdom of His Cause and the world of creation. Whoso achieveth this duty hath attained unto all good; and whoso is deprived thereof hath gone astray, though he be the author of every righteous deed. It behoveth everyone who reacheth this most sublime station, this summit of transcendent glory, to observe every ordinance of Him Who is the Desire of the world. These twin duties are inseparable. Neither is acceptable without the other. Thus hath it been decreed by Him Who is the Source of Divine inspiration.
    (Baha'u'llah: The Kitab-i-Aqdas, p. 19)

From the Writings of the Bab:
The Lord of the universe hath never raised up a prophet nor hath He sent down a Book unless He hath established His covenant with all men, calling for their acceptance of the next Revelation and of the next Book; inasmuch as the outpourings of His bounty are ceaseless and without limit.
    (The Bab: Selections from the Bab, p. 87)

From the Writings and Utterances of `Abdu'l-Baha:
His Holiness Abraham, on Him be peace, made a covenant concerning His Holiness Moses and gave the glad-tidings of His coming. His Holiness Moses made a covenant concerning the Promised One, i.e. His Holiness Christ, and announced the good news of His Manifestation to the world. His Holiness Christ made a covenant concerning the Paraclete and gave the tidings of His coming. His Holiness the Prophet Muhammad made a covenant concerning His Holiness the Bab and the Bab was the One promised by Muhammad, for Muhammad gave the tidings of His coming. The Bab made a Covenant concerning the Blessed Beauty of Baha'u'llah and gave the glad-tidings of His coming for the Blessed Beauty was the One promised by His Holiness the Bab. Baha'u'llah made a covenant concerning a promised One who will become manifest after one thousand or thousands of years. He likewise, with His Supreme Pen, entered into a great Covenant and Testament with all the Baha'is whereby they were all commanded to follow the Center of the Covenant after His departure, and turn not away even to a hair's breadth from obeying Him.
    (`Abdu'l-Baha: Baha'i World Faith, p. 358)

Baha'u'llah covenanted, not that I (Abdu'l-Baha) am the Promised One, but that Abdu'l-Baha is the Expounder of the Book and the Centre of His Covenant, and that the Promised One of Baha'u'llah will appear after one thousand or thousands of years. This is the Covenant which Baha'u'llah made. If a person shall deviate, he is not acceptable at the Threshold of Baha'u'llah. In case of differences, Abdu'l-Baha must be consulted. They must revolve around his good pleasure. After Abdu'l-Baha, whenever the Universal House of Justice is organized it will ward off differences.
    (`Abdu'l-Baha: The Covenant, p. 117)

Inasmuch as great differences and divergences of denominational belief had arisen throughout the past, every man with a new idea attributing it to God, Baha'u'llah desired that there should not be any ground or reason for disagreement among the Baha'is. Therefore, with His own pen He wrote the Book of His Covenant, addressing His relations and all people of the world, saying, "Verily, I have appointed One Who is the Center of My Covenant. All must obey Him; all must turn to Him; He is the Expounder of My Book, and He is informed of My purpose. All must turn to Him. Whatsoever He says is correct, for, verily, He knoweth the texts of My Book. Other than He, no one doth know My Book."
    (`Abdu'l-Baha: Promulgation of Universal Peace, pp. 322-323)

As to the most great characteristic of the revelation of Baha'u'llah, a specific teaching not given by any of the Prophets of the past: It is the ordination and appointment of the Center of the Covenant. By this appointment and provision He has safeguarded and protected the religion of God against differences and schisms, making it impossible for anyone to create a new sect or faction of belief. To ensure unity and agreement He has entered into a Covenant with all the people of the world, including the interpreter and explainer of His teachings, so that no one may interpret or explain the religion of God according to his own view or opinion and thus create a sect founded upon his individual understanding of the divine Words. The Book of the Covenant or Testament of Baha'u'llah is the means of preventing such a possibility, for whosoever shall speak from the authority of himself alone shall be degraded.
    (`Abdu'l-Baha: Promulgation of Universal Peace, pp. 455-456)

The first condition is firmness in the Covenant of God. For the power of the Covenant will protect the Cause of Baha'u'llah from the doubts of the people of error. It is the fortified fortress of the Cause of God and the firm pillar of the religion of God. Today no power can conserve the oneness of the Baha'i world save the Covenant of God; otherwise differences like unto a most great tempest will encompass the Baha'i world. It is evident that the axis of the oneness of the world of humanity is the power of the Covenant and nothing else. Had the Covenant not come to pass, had it not been revealed from the Supreme Pen and had not the Book of the Covenant, like unto the ray of the Sun of Reality, illuminated the world, the forces of the Cause of God would have been utterly scattered and certain souls who were the prisoners of their own passions and lusts would have taken into their hands an axe, cutting the root of this Blessed Tree. Every person would have pushed forward his own desire and every individual aired his own opinion! Notwithstanding this great Covenant, a few negligent souls galloped with their chargers into the battlefield, thinking perchance they might be able to weaken the foundation of the Cause of God: but praise be to God all of them were afflicted with regret and loss, and erelong they shall see themselves in poignant despair. Therefore, in the beginning the believers must make their steps firm in the Covenant so that the confirmations of Baha'u'llah may encircle them from all sides, the cohorts of the Supreme Concourse may become their supporters and helpers, and the exhortations and advices of Abdu'l-Baha, like unto the pictures engraved on stone, may remain permanent and ineffaceable in the tablets of all hearts.
    (`Abdu'l-Baha: Tablets of the Divine Plan, pp. 51-52)

From the Writings of Shoghi Effendi:
Referring to both the Guardian and the Universal House of Justice we read these emphatic words: "The sacred and youthful Branch, the Guardian of the Cause of God, as well as the Universal House of Justice to be universally elected and established, are both under the care and protection of the Abha Beauty, under the shelter and unerring guidance of the Exalted One (the Bab) (may my life be offered up for them both). Whatsoever they decide is of God."
    (Shoghi Effendi: World Order of Baha'u'llah, p. 149)

...They [Baha'u'llah and `Abdu'l-Baha] have ... in unequivocal and emphatic language, appointed those twin institutions of the House of Justice and of the Guardianship as their chosen Successors, destined to apply the principles, promulgate the laws, protect the institutions, adapt loyally and intelligently the Faith to the requirements of progressive society, and consummate the incorruptible inheritance which the Founders of the Faith have bequeathed to the world.
    (Shoghi Effendi: Lights of Guidance, p. 319)