The Hidden Words or Kalimát-i-Maknúnih was written in Baghdad around 1857-1858 by Mirza Husayn-‘Alí Núrí.
The text has the form of a collection of aphorisms or short writings – 71 in Arabic language and 82 in Persian (Farsi) – which deal with the essence of religious truth and the nature of man. The reader is invited to leave materialism behind and to elevate himself/herself spiritually. The author encourages his readers to nurture knowledge and justice, to love God, and to behave accordingly
The structure of the text is that of a dialogue in the first person; therefore the reader feels more intimately God’s closeness in a spiritually interactive relationship.
The Hidden Words are a compendium of thoughts without any particular order, in the Islamic form of a ḥadíth-qudsí, as if it were God’s voice «admonishing and advising all men». These thoughts show a way to inner perfection thanks to which every small human self can get closer to the reunification with the great holy self; at the same time they transmit profound reflections about the origin and the nature of man, about the relationship between man and God and the relationship among people, as well as about the meaning of human life, the understanding of which represents a stimulus and in a certain way a promise for whomever wants to undertake the spiritual way recommended by these thoughts. Also due to these characteristics, the Hidden Words was defined as a work «of unsurpassed preeminence among the … ethical writings» of Mirza Husayn-‘Alí Núrí.