《新唐书·列传·卷六十八》
陛下过去在灵武、凤翔时，没有今日的强兵而能杀敌，没有今日的法度限制却无人逃亡，没有今日的威严法令却无盗贼作案，没有今日的充足财用而百姓不流失，没有今日的爵位赏赐士大夫却不走散，没有今日的朝廷规模贤者却愿意效忠朝廷，这是什么原因呢？
陛下往在灵武、凤翔，无今日胜兵而能杀敌，无今日检禁而无亡命，无今日威令而盗贼不作，无今日财用而百姓不流，无今日爵赏而士不散，无今日朝廷而贤者思仕，何哉？
When your Majesty was in Lingwu and Fengxiang in the past, you did not have today's strong soldiers but you could kill the enemy, you did not have today's laws and regulations but no one escaped, you did not have today's majesty and laws but there were no robbers committing crimes, and you did not have today's ample funds, but the people did not flee, did not have today's titles and rewards for scholars but they did not scatter, did not have today's court size but the worthy people were willing to serve the court, what is the reason for this?