《旧唐书·列传·卷一百一十》
抵制异端邪说，排斥佛教道教，弥补儒学的缺漏，阐发儒学道统，独自旁搜博引将它从远古继承下来；犹如防堵百川泛滥而使它东流入海，挽回已经倾泻的狂澜。
牴排异端，攘斥佛、老；补苴罅漏，张皇幽眇；寻坠绪之茫茫，独旁搜而远绍；障百川而东之，回狂澜于既倒。
Resisting unorthodox and heretical teachings, rejecting Buddhism and Taoism, filling in the deficiencies of Confucianism, elucidating the orthodox tradition of Confucianism, he single-handedly searched far and wide, collecting and quoting from the past; just like blocking overflowing rivers and directing them east into the sea, turning the tide that had already been spilling over.