The Kitáb-i-Aqdas - The Most Holy Book
Index term: relationship to the Báb, under Bahá’u’lláh
k2.
They whom God hath endued with insight will readily recognize that the precepts laid down by God constitute the highest means for the maintenance of order in the world and the security of its peoples. He that turneth away from them is accounted among the abject and foolish. We, verily, have commanded you to refuse the dictates of your evil passions and corrupt desires, and not to transgress the bounds which the Pen of the Most High hath fixed, for these are the breath of life unto all created things. The seas of Divine wisdom and Divine utterance have risen under the breath of the breeze of the All-Merciful. Hasten to drink your fill, O men of understanding! They that have violated the Covenant of God by breaking His commandments, and have turned back on their heels, these have erred grievously in the sight of God, the All-Possessing, the Most High.
k110.
All Feasts have attained their consummation in the two Most Great Festivals, and in the two other Festivals that fall on the twin days -- the first of the Most Great Festivals being those days whereon the All-Merciful shed upon the whole of creation the effulgent glory of His most excellent Names and His most exalted Attributes, and the second being that day on which We raised up the One Who announced unto mankind the glad tidings of this Name, through which the dead have been resurrected and all who are in the heavens and on earth have been gathered together. Thus hath it been decreed by Him Who is the Ordainer, the Omniscient.
k175.
O Pen of the Most High! Move Thou upon the Tablet at the bidding of Thy Lord, the Creator of the Heavens, and tell of the time when He Who is the Dayspring of Divine Unity purposed to direct His steps towards the School of Transcendent Oneness; haply the pure in heart may gain thereby a glimpse, be it as small as a needle’s eye, of the mysteries of Thy Lord, the Almighty, the Omniscient, that lie concealed behind the veils. Say: We, indeed, set foot within the School of inner meaning and explanation when all created things were unaware. We saw the words sent down by Him Who is the All-Merciful, and We accepted the verses of God, the Help in Peril, the Self-Subsisting, which He [The Báb] presented unto Us, and hearkened unto that which He had solemnly affirmed in the Tablet. This we assuredly did behold. And We assented to His wish through Our behest, for truly We are potent to command.
k179.
Beware lest aught that hath been revealed in the Bayán should keep you from your Lord, the Most Compassionate. God is My witness that the Bayán was sent down for no other purpose than to celebrate My praise, did ye but know! In it the pure in heart will find only the fragrance of My love, only My Name that overshadoweth all that seeth and is seen. Say: Turn ye, O people, unto that which hath proceeded from My Most Exalted Pen. Should ye inhale therefrom the fragrance of God, set not yourselves against Him, nor deny yourselves a portion of His gracious favour and His manifold bestowals. Thus doth your Lord admonish you; He, verily, is the Counsellor, the Omniscient.
n108.
the Bayán
The Bayán, the Mother Book of the Bábí­ Dispensation, is the title given by the Báb to His Book of Laws, and it is also applied to the entire body of His Writings. The Persian Bayán is the major doctrinal work and principal repository of the laws ordained by the Báb. The Arabic Bayán is parallel in content but smaller and less weighty. When describing the Persian Bayán in God Passes By Shoghi Effendi indicated that it should be regarded "primarily as a eulogy of the Promised One rather than as a code of laws and ordinances designed to be a permanent guide to future generations".
‘Abdu’l-Bahá has written: “The Bayán hath been superseded by the Kitáb-i-Aqdas, except in respect of such laws as have been confirmed and mentioned in the Kitáb-i-Aqdas.”
n109.
the destruction of books
In the Tablet of Ishráqát Bahá’u’lláh, referring to the fact that the Báb had made the laws of the Bayán subject to His sanction, states that He put some of the Báb’s laws into effect “by embodying them in the Kitáb-i-Aqdas in different words”, while others He set aside.
With regard to the destruction of books, the Bayán commanded the Báb’s followers to destroy all books except those that were written in vindication of the Cause and Religion of God. Bahá’u’lláh abrogates this specific law of the Bayán.
As to the nature and severity of the laws of the Bayán, Shoghi Effendi in a letter written on his behalf provides the following comment:

The severe laws and injunctions revealed by the Báb can be properly appreciated and understood only when interpreted in the light of His own statements regarding the nature, purpose and character of His own Dispensation. As these statements clearly reveal, the Bábí­ Dispensation was essentially in the nature of a religious and indeed social revolution, and its duration had therefore to be short, but full of tragic events, of sweeping and drastic reforms. Those drastic measures enforced by the Báb and His followers were taken with the view of undermining the very foundations of Shí­'ih orthodoxy, and thus paving the way for the coming of Bahá’u’lláh. To assert the independence of the new Dispensation, and to prepare also the ground for the approaching Revelation of Bahá’u’lláh, the Báb had therefore to reveal very severe laws, even though most of them were never enforced. But the mere fact that He revealed them was in itself a proof of the independent character of His Dispensation and was sufficient to create such widespread agitation, and excite such opposition on the part of the clergy that led them to cause His eventual martyrdom.