In the 19th century, countless individuals believed a new Revelation was imminent. In Persia, the Báb fulfilled the prediction by several clerics of the appearance of the Promised Qa'im. Tahirih of Qazvin, a gifted teacher, was at the vanguard of spreading the Báb's teachings. She unceasingly proclaimed the Bábí Faith and brought a deeper understanding of its teachings to the rapidly growing numbers of its converts. Her vibrant poetry gave voice to her spiritual longing and passion, and its freshness reflected the vitality of the new spiritual teachings. She emerged as the most outspoken of the Babí leaders. The authorities responded by having her murdered in the dead of night. The memory of her life survives in her poems.

At the same time, many Americans believed the Second Coming of Christ was imminent. Several churches and movements emerged, some founded by women. Among them were Ellen G. White, a theological thinker who shaped the beliefs of the Adventist movement, Sojourner Truth, who came up from slavery to electrify audiences with her salvation preaching, and Mary Baker Eddy, founder of the Church of Christ Science; these women leaders were prefigured in the 18th century by 'Mother' Ann Lee, founder of the Shakers, and the long forgotten female 'exhorters'.

The Calling by Hussein Ahdieh and Hillary Chapman describes Tahirih in a fresh, new manner, juxtaposing and interweaving her life and work with that of her American contemporaries—women whose existence she was probably not aware of, but who shared with her a spiritual bond and vision of progress and justice.