In the Perlesvaus the conquest of the Grail Castle and in the Prose Lancelot the conquest of the Castle of Dolorous Guard both serve to establish the supremacy of the hero. The succession of events in the two recitals contains many parallels proving that they are closely related. The details of the Prose Lancelot are such as to show a probability that it used the Perlesvaus as a source. For instance, the despair of the besieged, but noncombatant, lords, demonstrated on the walls of their castles, is carried swiftly to suicide in the Perlesvaus, reduced to flight and suicidal behavior in the Prose Lancelot. Again, the three shields that give Lancelot marvelous strength and that differ in appearance only through the number of bands that decorate them celebrate nothing, though the whole episode stands as the crowning step in the process by which the Lady of the Lake brought the child whom she educated to acceptance as the best knight in the world. In the Perlesvaus the various supernatural aids all manifest la vertu de Deu in harmony with the sole purpose of that romance, the exaltation of Christianity.