杯弓蛇影（盃弓蛇影）　

◎ 杯弓蛇影 bēigōng-shéyǐng

[extremely suspicious;have imaginary fears as one who mistakes the reflection of a bow in the wine cup for the shadow of a snake] 应劭《风俗通义·怪神第九》记载,应郴请杜宣饮酒,挂在墙上的弓映在酒杯里,杜宣以为杯中有蛇,疑心中蛇毒而生病。后用“杯弓蛇影”比喻疑神疑鬼,妄自惊扰