《后汉书·列传·光武十王列传》
刘苍认为受恩过礼，情不自安，上疏辞谢道： 臣听说贵有常尊，贱有等威，卑高列序，上下以理。
苍以受恩过礼，情不自宁，上疏辞曰： 臣闻贵有常尊，贱有等威，卑高列序，上下以理。
Liu Cang thought that he had received too much favor and was uneasy, so he wrote a letter of excuse: I heard that the noble have constant respect, and the humble have equal authority. High and low are separated, and superiors and subordinates are reasonable.