This essay investigates the major topics of Paradiso, Canto XXXI, by paying particular attention to images and words deriving from Cistercian literature and medieval preaching. In describing the "candida rosa", Dante is inspired by the mystic symbolism of the commentaries on the Song of Songs written by St. Bernard and his school. Dante's physical description of St. Bernard refers to the famous portrait made by his biographer, Geoffroi d'Auxerres. St. Bernard's moral character ("benigna letizia", "atto pio / quale a tenero padre si convene") is evoked through Cistercian "affective" lexicon. Moreover, the essay considers some thirteenth-century preaching-related texts (Raoul de Chateauroux's Distinctiones) to show the Christological meaning of the French red and golden standard, the "orifiamma", which is a metaphor for the brightest spot in the Empireo reserved for Mary.