DURANDO of TROARN. - Benedictine abbot and theologian, born at the beginning of the 11th century, probably at Nantes, died 11 Feb. 1088 at Troarn (Normandy). A monk from 1031 at St-Wandrille, then at Fécamp, he won the favor of William, Duke of Normandy and King of England, who in 1059 appointed him abbot of St. Martin of Troarn (recently founded), where he governed wisely for 29 years, leaving a reputation as «a most skilled teacher of ecclesiastical song and divine doctrine, harsh to himself, but a gentle craftsman towards others» (Ordericus Vitalis [d. 1143], Hist. eccl., part 3, bk. 8: PL 188, 577).
Between 1050–58 he wrote the treatise *De corpore et sanguine Domini* (first published by d'Achery in Paris in 1688, appended to the works of Lanfranc, reprinted by Migne: PL 148, 1375–1424); it consists of 9 parts, developing the entire Catholic doctrine of the Eucharist, with occasional digressions and polemical thrusts against Berengar of Tours. Though occasioned by the heresy of the latter, the work as a whole maintains an irenic tone: avoiding particulars and subtle speculations (*credentium potius quam discutiendum*), the author prefers broad and synthetic visions of the truth, thus illuminating the idea of the *panis vitae* and showing its importance in the economy of salvation (*Christus illic est vitae locus, in quo vivat Christianus*). The work, rich in biblical and patristic texts, was an indirect but effective refutation of the nascent rationalistic Eucharistic theology of Berengar, of whom it also provides the first doctrinal details.