When Richard read this letter, he was at first in a dreadful rage, and he broke out into an explosion of the most violent, profane, and passionate language that can be conceived. Presently he looked at the letter again, and on reperusing it, and carefully considering its contents, he declared that he did not believe that Philip ever wrote it. It was a stratagem of Tancred's, he thought, designed to promote a quarrel between Richard and his ally. Tancred assured him that Philip did write the letter, or, at least, that it was brought to him as from Philip by the Duke of Burgundy, one of his principal officers. "You may ask the Duke of Burgundy," said he, "and if he denies it, I will challenge him to a duel through one of my barons." It was necessary that the parties to a duel, in those days, should be of equal rank, so that, if a king had a quarrel with a nobleman of another nation, he could only send one of his own noblemen of the same rank to be his representative in the combat. But this proposal of sending another man to risk his life in maintaining the cause of his king on a question of veracity, in which the person so sent had no interest whatever, illustrates very curiously the ideas of those chivalrous times. Richard did not go to the Duke of Burgundy, but, taking the letter which Tancred had shown him, he waited until he found a good opportunity, and then showed it to Philip. The two kings often fell into altercations and disputes in their interviews with each other, and it was in one of these that Richard produced the letter, offering it by way of recrimination to some charges or accusations which Philip was making against him. Philip denied having written the letter. It was a forgery, he said, and he believed that Richard himself was the author of it. "You are trying every way you can," said he, "to find pretexts for quarreling with me, and this is one of your devices. I know what you are aiming at: you wish to quarrel with me so as to find some excuse for breaking off your marriage with my sister, whom you are bound by a most solemn oath to marry. But of this you may be sure, that if you abandon her and take any other wife, you will find me, as long as you live, your most determined and mortal enemy." This declaration aroused Richard's temper, and brought the affair at once to a crisis. Richard declared to Philip that he never would marry his sister. "My father," said he, "kept her from me for many years because he loved her himself, and she returned his love, and now I will never have any thing to do with her. I am ready to prove to you the truth of what I say."