One of the most important books written by Bahá’u’lláh in Akka was the Kitab-i Aqdas (Most Holy Book). Written around 1873, it is essentially a book of laws and spiritual teachings. in citing the need for religious law, Bahá’u’lláh writes:
They whom God hath endued with insight will readily recognize that the precepts laid down by God constitute the highest means for maintenance of order in the world and the security of its peoples. – Bahá’u’lláh, Kitab-i Aqdas p.19.
The Kitab-i Aqdas contains guidance for the spiritual life of the individual Baha’i such as prayer, fasting, marriage, the education of children, and ethical teachings. It also creates the features of Baha’i community life such as the holding of periodic meetings, and the building of houses of worship with associated charitable trusts such as orphanages and homes for the aged. In the Kitab-i Aqdas, Bahá’u’lláh outlines the administrative institutions of the Baha’i Faith, which are elected bodies, while at the same time abolishing the institution of priesthood; in his social teachings he abolishes slavery, encourages charitable funds, exalts work to the rank of worship, enjoins his followers to associate with followers of all faiths in a spirit of friendliness, warns against fanaticism and bigotry, and calls upon all people to abandon whatever ideologies have caused them to shun one another.
Some of these laws were designed to be gradually implemented among Baha’is; others are designed for a future time envisioned Bahá’u’lláh when mankind becomes tired of the spiritual dearth of materialism, governments become threatened by the consequences of unrestrained nationalism, and people begin to seek spiritual solutions to the problems of the world. Using the metaphor of wine to describe the ecstacy of a soul intoxicated by the love of God, Bahá’u’lláh said of this book:
Think not that We have revealed unto you a mere code of laws. Nay, rather, We have unsealed the choice wine with the fingers of might and power. – Bahá’u’lláh, Kitab-i Aqdas p.21.
Other writings of Bahá’u’lláh, written in his later years, address the needs of humanity as a whole. The most important need Bahá’u’lláh identified was for unity. “Ye are all the leaves of one tree and the drops of one ocean.” This is a step beyond the Golden Rule.
The Golden Rule, which is found in all the major religions, teaches us to treat others as we would like to be treated. Bahá’u’lláh calls us to a higher understanding that we are all part of one reality. When we harm others, we are harming ourselves. Bahá’u’lláh compared the human race to the human body. If one part of the body is afflicted, for example, the entire body is threatened. This awareness links unity and peace with justice. In the words of Bahá’u’lláh:
The light of men is Justice. Quench it not with the contrary winds of oppression and tryanny. The purpose of justice is the appearance of unity among men. -Bahá’u’lláh, Tablets, pp.66-67.