《新唐书·列传·卷一百四十八》
当初，德宗皇帝刚即位，任崔甫为宰相，总是以道与德来引导皇帝的思想，所以建中初年纲纪肃然，赫然有贞观之风，及至卢杞为宰相，劝说皇帝以刑名来要求天下，叛乱及败政接踵而至，卢杞的狡诈阴毒，即使国事受挫、国主受辱，他依然恣肆妄为。
始，帝即位，以崔祐甫为相，专以道德导主意，故建中初纲纪张设，赫然有贞观风。及杞相，乃讽帝以刑名绳天下，乱败踵及。其阴害矫谲，虽国屯主辱，犹謷然肆为之。
When Emperor Dezong first assumed the throne, he appointed Cui Pu as prime minister, who often used morality and virtue to guide and influence the emperor. As a result, in the early years of Jianzhong, discipline was strict and the court had the air of the Zhenyuan era of Emperor Taizong. However, after Lu Qi became prime minister, he encouraged the emperor to use harsh criminal punishments to govern the world, leading to rebellions and upheaval. Lu Qi was so cunning and spiteful that even when the country was defeated and the emperor humiliated, he continued to run wild and act as he pleased.