Ruhi Book 2 (Persian) R13 Shoghi Effendi addressed this imperative

Shoghi Effendi addressed this imperative in a pivotal epistle to Western Bahá’ís—later published as “The Dispensation of Bahá’u’lláh” within The World Order of Bahá’u’lláh—clarifying the stations of the Central Figures and elucidating the twin institutions of the Guardianship and the Universal House of Justice

Seeing Double: The Covenant and the Tablet of Ahmad

fostering critical dialogue across cultural and religious boundaries

This is a relatively easy-to-read introductory book

Ruhi Book 2 (Persian) R13 Shoghi Effendi addressed this imperativeThe path of service and the essential features of community life are the main themes explored in Arising to Serve. Digital editions are free to download from the Ruhi Foundation website.