Gerard of Florennes (ca 975, bishop 1012[1] – 14 March 1051[2]), bishop of Cambrai as Gerard I, had formerly been chaplain to Henry II, Holy Roman Emperor, and helpful to the latter in his political negotiations with Robert the Pious, King of France. In 1024 Gerard called a synod in Arras to confront a purported heresy fomented by the Gundulfian heretics, who denied the efficacy of the Eucharist. The records of this synod, the Acta Synodi Atrebatensis,[3] preserve a summary of orthodox Christian doctrine of the early eleventh century, as well contemporary peace-making practices. According to this text's author, the heretics were convinced by Gerard's explanation of orthodoxy, renounced their heresy, and were reconciled with the church.
Gerard was the second son of Arnold, seigneur of Florennes in the county of Namur, the son of Godefroi, count of Hainaut, and thus a member of the high nobility of the Low Countries.[4]
He was a student of the great Gerbert of Aurillac, the leading theologian of the tenth century, and a supporter of the monastic reformer Richard of Verdun, abbot of Saint-Vanne.[5] In 1012, while he was a canon at Reims he founded the Abbey of Saint-Jean at Florennes, with Richard as its first abbot. At Florennes, on 12 September 1015, Godfrey II, Duke of Lower Lorraine, whose appointment Gerard had recommended to the Emperor, defeated both of his rivals, Lambert I, Count of Leuven, brother-in-law of Otto, and Reginar IV, count of Mons killing Lambert and forcing Reginar to make peace. In 1015, Gerard transferred the abbey to the church of Liège.[6] drawing together a community of monks from Verdun. Texts from the scriptorium show the innovative separation of words with spaces.[7]
Gerard was one of the theorists who justified the division of European society into the three estates of the realm, observing, as Georges Duby characterised his thought, "that there were distinctions between men, an essential inequality which could be compensated only by charity, mercy and mutual service" within the framework of divinely ordained natural law.[8] In addition to his role in the Investiture Controversy, Gerard was a voice in the implementation of the Peace and Truce of God movement to limit warfare.[9] At Douai in 1024 he introduced the Peace into Flanders at the urging of Count Baldwin IV, he himself apparently having reservations.[10]
During his episcopacy, the cathedral of Notre-Dame de Cambrai was reconsecrated, 18 October 1030.