What does romeo mean in these lines when he says, "i beseech thee, youth, / put not another sin upon my head / by urging me to fury"? what qualities do his words in this speech show?

Romeo does not want to fight Paris. He has no desire to take up arms against Paris; however, if Paris chooses to fight him, he will fight back. Romeo is characterized as noncombative. He doesn't want to fight Paris. We have seen this in other parts of the play as well. He did not want to fight Tybalt when Tybalt came at him. This choice was not a surprise because Romeo had shown to be rather passive in conversations about the fighting between the Capulets and Montagues. He never seemed to condone the fighting in the streets and seemed to stay out of the skirmishes. Romeo also comes across as very confident in his abilities as a swordsman. His statement that the fight will put "another sin upon [his] head" indicates that he is confident he will kill Paris if they fight.