And Zealot is part of a literary tradition that includes Albert Schweitzer ( The Quest of the Historical Jesus) and goes back to the Founding Fathers (Thomas Jefferson's The Life and Morals of Jesus of Nazareth Extracted Textually from the Gospels). Its contemporary proponents include New Testament scholar John Dominic Crossan, whose books include The Historical Jesus: The Life of a Mediterranean Jewish Peasant (1991).
"I'm synthesizing 200 years of scholarship on the historical Jesus and making it accessible," Aslan said from Hollywood, where he lives with his wife, entrepreneur Jessica Jackley, and their 2-year-old twin boys. "I am not saying all that much that hasn't been said by the scholars who came before me."
Was Jesus really an armed revolutionary? What about his message to love your enemies?
"Jesus is addressing Jews and talking about relations between Jews, not relations between Jews and Romans," Aslan said. "These terms have been transformed by Christians into abstract ethical principles."
Aslan, 41, has been a successful and well-received old-school popularizer of religious studies for nearly a decade. A student of the Abrahamic faiths acclaimed for his accessible writing on the intersection of religion and politics, he has produced an introduction to Islam ( No god but God: The Origins, Evolution, and Future of Islam) and a provocative, well-researched study of extremism ( Beyond Fundamentalism: Confronting Religious Extremism in the Age of Globalization).
Yet Zealot, his first book not about Islam, has been surrounded by a strange whirlwind of controversy, with critics questioning Aslan's credentials. They note that his doctorate is in sociology, not religion, and that he's a stranger to the study of Jesus and Christianity.
Things reached a nadir when Fox News' Lauren Green asked, in so many words, if a Muslim is qualified to write about Jesus.
Very few, if any, of the critics have mentioned that Aslan has firsthand experience: Born to Muslim parents, he joined an evangelical Protestant church in high school. He left when he began college and had what he calls "an intellectual conversion to Islam."
What's more, Aslan earned his bachelor's degree in religious studies from Santa Clara University in New Testament studies. He has a master of theological studies degree in world religions from Harvard University, and his Ph.D. is very much about religion.
Aslan earned the degree at the University of California, Santa Barbara, which is famous for its interdisciplinary program - students tailor their studies around a topic, not a department. They choose a department only for the diploma.
Notoriety also leads to sales: Now in its eighth printing (280,000 copies have been released), Zealot has made the New York Times bestseller list for eight consecutive weeks.
Aslan suggested that the news media were partly to blame because they pigeonholed him years ago as an expert in Islam, and Islam only. "I want to be as clear as possible: I'm not an expert on Islam. I write about religion and the Middle East," he said.
The problem with the Zealot controversy is that the book's real problems are lost in the general hysteria, as is the doomed nature of the project.
Establishing with any certainty a picture of the historical Jesus is a near-impossibility, since so little evidence has survived.
"It's true that many scholars have abandoned the entire quest for the historical Jesus because they believe the Jesus of history has become inaccessible to us," Aslan said.
"I disagree. I think if you place Jesus firmly in the historical context . . . you can make very educated hypotheses and guesses about how he lived."
You be the judge.
Reza Aslan: "Zealot: The Life and Times of Jesus of Nazareth"
Wednesday 7:30 p.m. at the Free Library of Philadelphia, 1901 Vine St.
Tickets: $15, $7 students.
Contact Tirdad Derakhshani at 215-854-2736 or firstname.lastname@example.org.