Wikipedia page about this book: https://en.wikipedia.org/wiki/Kit%C3%A1b-i-%C3%8Dq%C3%A1n

Release date is 2005-11-02

"The Kitáb-i-Íqán" by Bahá'u'lláh is a theological work written in 1861. Composed in Baghdad over two days and nights, this book addresses fundamental questions about divine revelation and religious truth. It argues that all major religions are connected through progressive revelation, each prophesying the next. Through biblical and Quranic interpretation, it demonstrates how sacred texts can be understood allegorically to recognize new messengers of God, ultimately defending the mission of the Báb while containing veiled references to Bahá'u'lláh's own station. (This is an automatically generated summary.)

Original publication data not identified