《隋书·列传·卷二十七》
柳彧弹劾他说： 我听说，天地之位分开，夫妇之礼这才清楚，君亲之义这才明白，尊卑之教这才设立。
彧劾之曰： 臣闻天地之位既分，夫妇之礼斯著，君亲之义生焉，尊卑之教攸设。
Liu Yu impeached him, saying: I have heard that the positions of heaven and earth are separate, the rituals of husband and wife are clear, the righteousness of monarch and relatives is understandable, and the teachings of respect and inferiority are established.