Bahá’u’lláh’s book of laws, written in Arabic around 1873 while He was still imprisoned within the city of ‘Akká. It was supplemented by later Writings and by Bahá’u’lláh’s replies to a series of questions posed by one of His secretaries. The first authorized English translation was published in 1992, annotated and accompanied by the supplementary Writings and the questions and answers.