《后汉书·列传·桓荣丁鸿列传》
从前的先师感谢弟子的有人了，上则通达经旨，弄明章句，下则去家慕乡，求谢师门。
昔之先师谢弟子者有矣，上则通达经旨，分明章句，下则去家慕乡，求谢师门。
In olden days, there were disciples who thanked their teachers. Some went to the top and mastered the scriptures and understood the meaning of each sentence, and those on the bottom went home to their families and asked the teacher to leave.