Brian McLaren is a leading Evangelical pastor and author of several books including “A Generous Orthodoxy,” “Why Did Jesus, Moses, the Buddha, and Mohammed Cross the Road?,” and the forthcoming “We Make the Road by Walking.” This interview is edited and produced with music and other features in the On Being episode “Brian McLaren — The Equation of Change.” Find more at onbeing.org.

“Let’s go back and look at our faith before it was reduced to a system, before it was reduced to a system of abstractions and beliefs. How can we rediscover our faith as a series of stories and as a series of encounters?” Brian McLaren on the evolution of Christianity and the meaning of progressive Evangelicalism.

Sherwin Nuland was a clinical professor of surgery at Yale University, where he also taught bioethics and medical history. His books include “How We Die,” “Lost in America,” “Maimonides,” and “How We Live: The Wisdom of the Body.” This interview is edited and produced with music and other features in the On Being episode “Sherwin Nuland — The Biology of the Spirit.” Find more at onbeing.org.

Dr. Sherwin Nuland died this week at the age of 83. He became well-known for his first book, “How We Die,” which won the National Book Award. For him, pondering death was a way of wondering at life — and the infinite variety of processes that maintain human life moment to moment. He reflects on the meaning of life by way of scrupulous and elegant detail about human physiology.

Bobby McFerrin is a ten-time Grammy Award winner. He is one of the world’s best-known vocal innovators and improvisers, a world-renowned classical conductor, and a passionate spokesman for music education. This interview is edited and produced with music and other features in the On Being episode “Bobby McFerrin — Catching Song.” Find more at onbeing.org.

He is a genius of improvisation; a genre-bending vocal magician and conductor. And he sings the territory between music, mystery, and spirit. Who better to contemplate the human voice — its delights, its revelations, and its mystery — than Bobby McFerrin?

Paul Elie is a senior fellow with the Berkley Center for Religion, Peace, and World Affairs and the director of the American Pilgrimage Project. His books include “The Life You Save May Be Your Own: An American Pilgrimage” and “Reinventing Bach.” This interview is edited and produced with music and other features in the On Being episode “Paul Elie — Faith Fired by Literature.” Find more at onbeing.org.

The writers Flannery O’Connor and Walker Percy, social activist Dorothy Day, and the Trappist monk Thomas Merton — all four shared a complex Catholic faith. Paul Elie takes us on a kind of literary pilgrimage through a Catholic imagination that still resonates in our time.

David Hartman was an Orthodox rabbi and founder of the Shalom Hartman Institute in Jerusalem. He authored many books, including “A Heart of Many Rooms” and “The God Who Hates Lies.” This interview is edited and produced with music and other features in the On Being episode “David Hartman — Hope in a Hopeless God.” Find more at onbeing.org.

David Hartman died a year ago this week. The Orthodox rabbi was a charismatic and challenging figure in Israeli society, called a “public philosopher for the Jewish people” and a “champion of adaptive Judaism.” We remember his window into the unfolding of his tradition in the modern world — Judaism as a lens on the human condition.