Clairvaux, Abbot and Doctor) Double White Vestments Saint Bernard of Clairvaux,  depicted in a Mediaeval manuscript. Bernard of Clairvaux, O.Cist (1090 – August 20, 1153) was a French abbot and the primary builder of the reforming  Cistercian  Order. After the death of his mother, Bernard sought admission into the Cistercian Order. Three years