His ruling passion was to convert all Islam to Christianity.

Yet, in a fit of rage, he slaughtered his Muslim ally who taught him Arabic.

He was a tireless peregrinator, traveling to many distant Islamic outposts. But his efforts were often met with stern opposition. The people he sought to convert responded with varying degrees of violence. He was detained, incarcerated, exiled, stoned and perhaps, as many believe, martyred by Saracens. He published the works of prominent Islamic thinkers and fought to include Islamic studies in Christian schools.

If passion and dedication were sufficient to justify ascension to the position of “patron saint of Christian-Muslim relations,” Ramón Llull would easily qualify.

Ramón Llull was born in the year 1232 (or thereabouts) in the Mediterranean island of Majorca. His father, a wealthy merchant from Barcelona, settled in Majorca with James I of Aragon the year after the king had conquered the island from the Moors. In effect, Llull was a child of Muslim-Christian inheritance. He was raised and educated at court and was eventually appointed a seneschal (a steward in charge of the royal palace) to the young James II. Traditional accounts tell colorful stories of Llull, especially in his role as a troubadour.

Llull was once smitten by a young woman. True to his romantic and flamboyant nature, he rode his horse into the center of the church where she was praying during a worship service in order to impress her with his love. She had her chaperon arrange an appointment and, when alone with Llull, confessed her own affection for him. In a most dramatic gesture, she then exposed that portion of her body that was already ravaged by cancer. She had only a few weeks to live. The impact on Llull was staggering and left him, for some time, in a state of emotional shock.

Sometime thereafter, after having been inspired by a Franciscan sermon, Llull renounced his life at court and dispossessed himself of all his worldly goods. He made pilgrimages to Rocamadour, Santiago de Compostela and other shrines, and subsequently joined the Franciscan order. In 1263 or 1264, Llull had repeated visions of Christ crucified. It was as a consequence of these mystical experiences that he conceived the idea that he had been chosen to convert Islam to Christianity.

In order to take the first step in achieving this grandiose project, he needed to learn Arabic. To this end, he secured the services of an Arab slave to teach him the language. When this task was accomplished and Llull had some command of the slave's mother tongue, he attempted to convert his teacher to Christianity.

Llull failed miserably. In his extreme frustration, whatever the particulars of the circumstance may have been, he flew into a rage and killed his slave. His remorse over such an impetuous and violent act caused so profound a remorse in him that he vowed that, from that moment on, he would live by only one rule: “He who loves not lives not.” Forevermore, he abandoned the sword to live by love and to persuade by logic.

From this point on, Llull's life is an icon of exuberance and indefatigability. His love for the Church and his enthusiasm for converting Muslims never diminished. On the academic side, his accomplishments were astonishing. He wrote 228 books on almost every important topic of his age. He wrote on philosophy, geometry, astronomy, physics, chemistry, anthropology, law, statecraft, navigation, horsemanship and warfare. He perfected the astrolabe, anticipated problems in thermodynamics and held strong to the position that there was a great continent on the other side of the world. He was also, apart from being a prolific logician, a very good poet and a novelist of considerable acclaim.

In addition to all this, Llull initiated the cult of the Virgin and provided the philosophical underpinning for the doctrines of the Immaculate Conception and the Assumption. There is a stained-glass window in one of the churches in Palma, the capital of Majorca. It shows St. Francis and St. Dominic watching with approval as Ramón Llull in purple robes and Duns Scotus in blue announce their doctrine of the Virgin.

“I revere Llull,” James Michener once wrote, “because in his day he saw the interlocking nature of the world and was willing to sacrifice his life to help achieve unity. To him the Mediterranean was infinitely larger than the Atlantic and the Pacific are to me, yet he went forth to all the shores, preaching one message, ‘He who loves not, lives not.’”

Llull lived well into his 80s. He died in the year 1316, perhaps, as many believe (particularly Franciscans) as a martyr. Some of the local gentry venerate him as a saint. The Encyclopedia Britannica states that irate Muslims stoned him to death outside the city walls of Bougie in Africa. The Catholic Encyclopedia claims that he was stoned to death by Saracens during his visit to Tunisia.

This great figure, Doctor Illuminatus, as he is called, is entombed on the Island of Majorca, his birthplace, in the convent dedicated to another troubadour and exuberant Christian, St. Francis of Assisi. In his life following his one grievous act of sin, he is a role model for our post-9-11 times.

Donald DeMarco is professor emeritus of philosophy at St. Jerome's University in Waterloo, Ontario.