《后汉书·列传·郭杜孔张廉王苏羊贾陆》
起先，禁令还比较简单，但凭盖了印章的玺书发兵，没有虎符作为信物。杜诗上书说： 我听说兵是国家的凶器，圣人是很慎重的。
初，禁网尚简，但以玺书发兵，未有虎符之信，诗上疏曰： 臣闻兵者国之凶器，圣人所慎。
 Initially, the prohibition order was relatively simple, but it was just to issue troops with the sealed imperial edict, without the tiger talisman as a token. Du Shi wrote: I heard that soldiers are the country's fierce weapons, and saints are very cautious.