The works of Ādi Śaṅkarācārya

Sanatsujātīyam

p. 181

p. 181

सत्यमुपलभ्यते; तथापि नासौ साक्षान्मृत्युः ।कस्तर्हि ? यः प्रमादाख्यो मृत्युः अज्ञानं स एव, साक्षाद्विनाशहेतुत्वात् ।तथा अज्ञानस्य विनाशहेतुत्वं श्रूयते ‘न चेदिहावेदीन्महती

In plain words

Granted, that is what one observes. Even so, that is not death in the direct sense. Then what is? The death that goes under the name pramāda, heedlessness — ignorance, precisely that, because ignorance is directly what destroys. And scripture says exactly this of ignorance: "If a person has not known it here, great..."

Close to the Sanskrit

True, it is apprehended; nevertheless, that is not death in the direct sense. What, then, is? That death which is named heedlessness — ignorance, that very thing is it, because of its being directly the cause of destruction. And accordingly, ignorance's being the cause of destruction is heard in scripture: "If one has not known it here, great [is the destruction]..."