PETER LOMBARD, (c. 1100-1160), bishop of Paris, better known as Magister Sententiarum, the son of obscure parents, was born about the beginning of the 12th century, at Novara (then reckoned as belonging to Lombardy). After receiving his education in jurisprudence and the liberal arts at Bologna, he removed to France, bearing a recommendation to Bernard of Clairvaux, who first placed him under Lotolf at Rheims, and afterwards sent him to Paris with letters to Gilduin, ,the abbot of St Victor. His diligence and talents soon brought him into notice, and ultimately obtained for him a theological chair, which he held for a number of years; during this period he is said to have been the first to introduce theological degrees. On June 29, 1159, he succeeded his former pupil, Philip, brother of Louis VII., in the bishopric of Paris, but did not long survive the promotion; according to the most trustworthy of the meagre accounts we have of his life, he died on July 20 of the following year.

His famous theological handbook, Sententiarum Libri Quatuor, is, as the title implies, primarily a collection of " sententise patrum." These are arranged (professedly on the basis of the aphorism of Augustine, Lombard's favourite authority, that " omnis doctrina vel rerum est vel signorum") into four books, of which the first treats of God, the second of the creature, the third of the incarnation, the work of redemption, and the virtues, and the fourth of the seven sacraments and eschatology. It soon attained immense popularity, ultimately becoming the text-book in almost every theological school, and giving rise to endless commentaries. A charge of heresy ("nihilianism") was indeed raised against Lombard for a particular view which he seemed not remotely to have indicated regarding Christ's human nature, but neither at the synod of Tours, where the question was first broached in 1163, nor at the subsequent Lateran synod in 1179, does a condemnation seem to have been obtained. In 1300 the theological professors of Paris agreed in the rejection of sixteen propositions taken from Lombard, but their decision was far from obtaining universal currency.

Besides the Sententise,, Lombard wrote numerous commentaries (e.g., on the Psalms, Canticles, Job, the Gospel Harmony, and the Pauline Epistles), sermons and letters, which still exist in MS. The Glossse seu Cmmnentarius in Psalmos Davidis, first published at Paris in 1533, and the Collectanea in omnes D. Pauli Epistolas (Paris, 1535) have been reprinted by Migne.