《太平御览》卷二十三引汉·应劭《风俗通·怪神》记载:汲县令应郴在夏至日请主薄杜宣来家饮酒。家里墙上挂着一张弓,弓照在酒杯里,影子像一条蛇。杜宣以为酒里有蛇,非常惊恐,但又不敢不饮。回家后便大病一场,久治不愈。应郴知道这个情况后,又请病中的杜宣来家饮酒,仍坐原处,杯中仍有蛇影。应郴对杜宣说:“此壁上弩影耳,非有他怪。”杜宣疑虑顿消,病也随之痊愈。后遂用“杯弓蛇影”比喻疑神疑鬼,自相 “Taiping Yu Lan” volume twenty-three cited Han Ying 劭 “customs through the weird god” records: Ji County should Chen Shadui home in the summer solstice Du Xuan home. There was a bow on the wall at home, the bow shone in the glass, and the shadow was like a snake. Du Xuan thought there was a snake in the wine, very scared, but dared not drink. Home after a serious illness, long treatment. Chen should know this situation, but also sick Du Xuan home drinking, still sit in the same place, the cup is still a snake shadow. Ying Chen Du Xuan said: “This wall crossbow Ying ears, non-strange him.” Du Xuan doubts disappear, the disease will also be cured. Then use “Cup bow snake ” analogy suspicious, self-phase