42 Preface يَومَ يُكشَفُ عَن ساقٍ وَيُدعَونَ إِلَى السُّجودِ فَلا يَستَطيعونَAli Quli QaraiThe day when the catastrophe occurs,1 and they are summoned to prostrate themselves, they will not be able [to do it]. Literally, ‘when the shank is uncovered,’ an idiom implying the occurrence of a calamity, or a disclosure and denouement.