子貢 Zǐgòng was arguably Confucius’s most successful student. Confucius sometimes seemed to worry that things came too easily to him. See Analects 1.15–16, 5.9, and 19.23. Zigong started life as a merchant and ended as a diplomat. According to Sima Qian, he was intimately involved in the drama between Wu and Yue, and, if so, may have been a moving force in the intrigue of the Warring States.
He appears in 6:06, where he attends the funeral of Master Mulberry-home. When he is appalled by the behavior of the remaining friends, Confucius explains to him that such people wander outside the rules. In 17:03, he encounters an old man watering his fields by hand. When Zigong tells him about the well-sweep, the old man sends him away. In 18:01, Confucius tells him he worries Yan Hui has gotten in over his head in Qi.