In the book "Le Morte d'Arthur, written by Sir Thomas Malory about the adventures of King Arthur, the author draws a level of parallelism between Arthur's internal and external conflicts with Lancelot and his conflicts with Mordred.
Although both characters represents different types of conflict in Arthur, the resolution he decides for both of them is the same. This being revenge. He wants revenge on Lancelot because of the adultery this last one has committed with the Queen, Guinevere. He also seeks revenge on Mordred because of the intentions that Mordred has to seek the Throne, that belongs to King Arthur.
But they are different in the sense that King Arthur does not desire to have a fight with the character of Lancelot, but indeed he wants to battle Mordred.