[12] During his tenure, the General Chapter of Narbonne, held in 1260, promulgated a decree prohibiting the publication of any work out of the order without permission from superiors.

In 1254 Gerard had published without permission a work, Introductorius in Evangelium æternum (An Introduction to the Eternal Gospel) that was judged heretical within a year.

[13] Bonaventure was instrumental in procuring the election of Pope Gregory X, who rewarded him with the title of Cardinal Bishop of Albano, and insisted on his presence at the great Second Council of Lyon in 1274.

He thought of Christ as the "one true master" who offers humans knowledge that begins in faith, is developed through rational understanding, and is perfected by mystical union with God.

[15] The only extant relic of Bonaventure is the arm and hand with which he wrote his Commentary on the Sentences, which is now conserved at Bagnoregio, in the parish church of St.

[17] His works, as arranged in the most recent Critical Edition by the Quaracchi Fathers (Collegio S. Bonaventura), consist of a Commentary on the Sentences of Lombard, in four volumes, and eight other volumes, including a Commentary on the Gospel of St Luke and a number of smaller works; the most famous of which are The Mind's Road to God (Itinerarium mentis in Deum), an outline of his theology or Brief Reading (Breviloquium), Reduction of the Arts to Theology (De reductione artium ad theologiam), and Soliloquy on the Four Spiritual Exercises (Soliloquium de quatuor mentalibus exercitiis), The Tree of Life (Lignum vitae), and The Triple Way (De Triplici via), the latter three written for the spiritual direction of his fellow Franciscans.

[19][20] A work that for many years was falsely attributed to Bonaventure, De septem itineribus aeternitatis, was actually written by Rudolf von Biberach (c. 1270 – 1329).

[6] The Commentary on the Sentences, written at the command of his superiors when he was twenty-seven,[17] is Bonaventure's major work and most of his other theological and philosophical writings are in some way dependent on it.

No work of Bonaventure's is exclusively philosophical, a striking illustration of the mutual interpenetration of philosophy and theology that is a distinguishing mark of the Scholastic period.

[17] Much of Bonaventure's philosophical thought shows a considerable influence by Augustine of Hippo, so much so that De Wulf considers him the best medieval representative of Augustinianism.

Bonaventure adds Aristotelian principles to the Augustinian doctrine, especially in connection with the illumination of the intellect and the composition of human beings and other living creatures in terms of matter and form.

While these may be taken as representing, respectively, physical science yet in its infancy, and Aristotelian scholasticism in its most perfect form, Bonaventure presents the mystical and Platonizing mode of speculation that had already, to some extent, found expression in Hugo and Richard of St. Victor, Alexander of Hales, and in Bernard of Clairvaux.

This also serves as his repudiation of Arab peripatetic necessitarianism and pure Aristotelian identified by the Greek Fathers, if left uncorrected by Plato and Revelation which teach the same thing under different modes.

To obtain this illumination, the soul must employ the proper means, which are prayer; the exercise of the virtues, whereby it is rendered fit to accept the divine light; and meditation that may rise even to ecstatic union with God.

[10] Like Aquinas and other notable thirteenth-century philosophers and theologians, Bonaventure believed that it is possible to logically prove the existence of God and the immortality of the soul.

[32] A master of the memorable phrase, Bonaventure held that philosophy opens the mind to at least three different routes humans can take on their journey to God.

Non-intellectual material creatures he conceived as shadows and vestiges (literally, footprints) of God, understood as the ultimate cause of a world that philosophical reason can prove was created at a first moment in time.

[Bonaventure] teaches us that each creature bears in itself a specifically Trinitarian structure, so real that it could be readily contemplated if only the human gaze were not so partial, dark and fragile.

[34]Bonaventure, however, is not only a meditative thinker, whose works may form good manuals of devotion; he is a dogmatic theologian of high rank, and on all the disputed questions of scholastic thought, such as universals, matter, seminal reasons, the principle of individuation, or the intellectus agens, he gives weighty and well-reasoned decisions.

He agrees with Albert the Great in regarding theology as a practical science; its truths, according to his view, are peculiarly adapted to influence the affections.

This fact affects his importance as a philosopher; when coupled with his style, it makes Bonaventure perhaps the least accessible of the major figures of the thirteenth century.