Although Cao Cao admired Guan Yu's character, he also sensed that Guan Yu had no intention of serving under him for long. He told Zhang Liao, "Why don't you make use of your friendship with Guan Yu to find out what he wants?" When Zhang Liao asked him, Guan Yu replied, "I am aware that Lord Cao treats me very generously. However, I have also received many favours from General Liu and I have sworn to follow him until I die. I cannot break my oath. I will leave eventually, so maybe you can help me convey my message to Lord Cao." Zhang Liao did so, and Cao Cao was even more impressed with Guan Yu. The "Fu Zi" gave a slightly different account of this incident. It recorded that Zhang Liao faced a dilemma of whether or not to convey Guan Yu's message to Cao Cao: if he did, Cao Cao might execute Guan Yu; if he did not, he would be failing in his service to Cao Cao. He sighed, "Lord Cao is my superior and he is like a father to me, while Guan Yu is like a brother to me." He eventually decided to tell Cao Cao. Cao Cao said, "A subject who serves his lord but doesn't forget his origins is truly a man of righteousness. When do you think he will leave?" Zhang Liao replied, "Guan Yu has received favours from Your Excellency. He will most probably leave after he has repaid your kindness."