jì yǒu jīn rì,hé bì dāng chū
既然现在后悔,当初为什么要那样做?
《五灯会元·天衣怀禅师法嗣·惠林宗本禅师》:“曰:‘中下之流,如何领会?’师曰:‘伏尸万里。’曰:‘早知今日事,悔不慎当初。’”
既有今日,何必当初作谓语、分句;用于数落人。
if there must be today,then why should there have been other days