Still as strange, controversial, and influential as it was nearly 2,000 years ago, the biblical Book of Revelation is a fountainhead of “visions and dreams and nightmares,” said Elaine Pagels.

The Princeton University professor of religion, famous for infusing old religious debates with new urgency, was at Harvard Dec. 3 to share what she called “a quick mad dash” of her latest thinking on Revelation, its cultural impact, and its historical underpinnings.

The occasion was the first session of this year’s Dean’s Lecture Series at the Radcliffe Institute for Advanced Study.

Revelation, the final book in the New Testament, was “squeezed into the canon in the fourth century,” said Pagels, and barely made it into the 27-book lineup. Over the centuries, it continued to draw the ire of critics, from theologian Martin Luther to author D.H. Lawrence. To this day, Eastern Orthodox Christian sects decline to use Revelation in public worship.

At the center of the long controversy is Revelation’s language, which is both concretely powerful and powerfully indirect. Christ appears as a terrifying warrior clad in white. Satan is a great red dragon waiting to devour a newborn child. The Whore of Babylon, “drunken with the blood of saints,” is astride a scarlet beast with seven heads and 10 horns. A great lake of fire and brimstone opens up, ready to consume a long catalog of unbelievers.

Pagels is exploring a range of questions. Who wrote this book, and why? Among the 30 or so similar books that appeared in the first through third centuries, why did this one survive? How is it still influential?

During her lecture at Radcliffe Gymnasium to an unusually large crowd of 250, she made a direct appeal for help from the audience.

But first Pagels gave a guided tour of Revelation, complete with artistic treatments through the ages, from Hieronymus Bosch, Albrecht Dürer, and William Blake to Roger Brown, James Hampton, and Robert Roberg. She said its author was John of Patmos. Exiled on a small island off the coast of present-day Turkey around the year 90 CE, she said, John wrote Revelation while “in the spirit.”

That would explain the tumbling rush of images so famous now in apocalyptic literature: Revelation’s slaughter, plague, famine, and catastrophe on the backs of dragons, and armies of good and evil warriors so vast they were in number like “the sands of the sea.”

History appears to have been a powerful influence on John, including the then-recent Jewish uprising against Rome (66-70 CE), which led to the destruction of Jerusalem by victorious Roman armies. “We can’t understand this book,” said Pagels of Revelation, “unless we know it is war literature.”

Traditional prophets, Isaiah among them, had centuries before predicted Babylon would destroy Jerusalem. John of Patmos simply modernized the old prophecies, said Pagels, using Isaiah’s corrupt Babylon as an allegory for what was then present-day Rome.

“Jews would typically write in a kind of code,” she said, unleashing hellfire on a present-day enemy, but obliquely. Revelation, in a touch of irony, was written to be not too revealing.

Along the way, Pagels used a handout to illustrate a “tiny, miscellaneous, hors d’oeuvres sample” of the other Revelation-like books that were written in the three centuries following the death of Christ.

These texts — all now obscure and little studied — promoted ideas that threatened an evolving Christian orthodoxy. They included the idea that divine power had a feminine aspect. The handout included a snippet from “The Gospel of Mary” and one from “Trimorphic Protennoia,” a reflection on “she in whom the All takes its stand.”

Other texts suggested another unorthodox idea for the time: that in each person is a divine light. “The Thunder” includes a line, “I am the hearing that can be grasped by everyone.”

Another idea in these little-known texts is that authority can be questioned. In “The Revelation of Ezra,” the prophet Ezra is despondent over the ascendency of Babylon. An angel visits, giving Ezra three tasks intended to show how little he knows of the world: weigh fire, measure the wind, and bring back the day that is past.

But instead of falling silent, as the Biblical Job did, Ezra is “the anti-Job,” said Pagels. “He keeps asking questions.” Ezra also goes on to express a perspective that has modern resonance. “I did not wish to inquire about the ways above, but about those things which we daily experience and why we die like insects. …”

So why was the Revelation we know elevated to the New Testament canon? Why was it so appealing, and how, 2,000 years later, does it remain so influential?

One reason was John’s writing technique, said Pagels, which shifted perspective from heaven to Earth and back again. By providing God’s perspective of events on Earth, she said, John suggested that evil would not prevail and would be avenged.

Then there is the “wildly imaginary garden” of Revelation, peopled by “real beasts,” said Pagels, devils and whores and dragons that represent “the emperors and soldiers who killed and humiliated” so many Jews. If the images had been “tied to one person or event,” that is, identified clearly, she said, John’s vivid allegory of evil and revenge “would simply be an antiquarian book.”

Pagels offered a third theory for the survival and prominence of Revelation: that it suggests there is moral meaning in human conflict.

Evoking fear and then hope invites people “to make sense out of conflict and struggle,” she said, offering as proof a quick survey of how Revelation’s message of good and evil has been employed over two millennia.

Revelation’s Four Horsemen rode back to medieval Europe, when the Black Death killed a third of the population.

The Antichrist reappeared as Martin Luther to his critics. To Lutherans, the Whore of Babylon was recast as the Pope of Rome.

Revelation’s good-and-evil imagery came back to represent the religious wars of Europe, the rise of Napoleon, and even the American Civil War, in which each side appropriated the serpent of Satan to represent the other.

Social philosopher Thomas Hobbes used the biblical Leviathan as an image of contemporary society, and London’s detractors saw it as a new Babylon. During World War II, Nazi leader Adolf Hitler was portrayed as Satan’s voracious serpent, being repelled by a host of angel-like Allies, of course.

To bring Revelation’s power nearly to the present, Pagels showed an aerial image of Baghdad in April 2003 being battered by the shock and awe of U.S. bombs — right at the spot over the Euphrates River where a New Testament angel pours the cup of God’s wrath.

In her previous books, Pagels has challenged orthodox interpretations of Adam and Eve, Satan, and Judas. Perhaps most famously, she has argued that Christ saw himself not as the deity, but as a teacher eager to have people feel the light of God in themselves.

In the footsteps of Du Bois