"[9][10] In 1976, Armstrong took a job teaching English at James Allen's Girls' School in Dulwich while working on a memoir of her convent experiences.

In 1984, the British Channel Four commissioned her to write and present a television documentary on the life of St. Paul, The First Christian, a project that involved traveling to the Holy Land to retrace the steps of the saint.

Armstrong described this visit as a "breakthrough experience" that defied her prior assumptions and provided the inspiration for virtually all her subsequent work.

In A History of God: The 4,000-Year Quest of Judaism, Christianity and Islam (1993), she traces the evolution of the three major monotheistic traditions from their beginnings in the Middle East up to the present day and also discusses Hinduism and Buddhism.

As guiding "luminaries" in her approach, Armstrong acknowledges (in The Spiral Staircase and elsewhere) the late Canadian theologian Wilfred Cantwell Smith, a Protestant minister,[11] and the Jesuit father Bernard Lonergan.

In the year of its publication Armstrong was invited to choose her eight favourite records for BBC Radio's Desert Island Discs programme.

[15] Armstrong is a fellow of the Jesus Seminar, a group of scholars and laypeople which attempts to investigate the historical foundations of Christianity.

"[17] She maintains that religious fundamentalism is not just a response to, but is a product of contemporary culture[18] and for this reason concludes that, "We urgently need to make compassion a clear, luminous and dynamic force in our polarized world.

"[19] Awarded the $100,000 TED Prize in February 2008, Armstrong called for drawing up a Charter for Compassion, in the spirit of the Golden Rule, to identify shared moral priorities across religious traditions, in order to foster global understanding and a peaceful world.

[21] In 2012, the Jack P. Blaney Award for Dialogue recognized her outstanding achievement in advancing understanding about and among world religions, and promoting compassion as a way of life.

During her award residency in Canada, Armstrong gave the "State of the Charter for Compassion Global Address" and co-launched a compassionate cities initiative in Vancouver.

The institute stated that Armstrong had become "a significant voice, seeking mutual understanding in times of turbulence, confrontation and violence among religious groups."

It cited "her personal dedication to the ideal that peace can be found in religious understanding, for her teachings on compassion, and her appreciation for the positive sources of spirituality.

Through a series of books and award-winning lectures she reaches out as a peace-making voice at a time when world events are becoming increasingly linked to religion."

[36] Armstrong was described by philosopher Alain de Botton as "one of the most intelligent contemporary defenders of religion", who "wages a vigorous war on the twin evils of religious fundamentalism and militant atheism".