Mahabharata 12.309.20

क्रमशः संचितशिखो धर्मबुद्धिमयो महान्अन्धकारे प्रवेष्टव्ये दीपो यत्नेन धार्यताम्

kramaśaḥ saṃcitaśikho dharmabuddhimayo mahānandhakāre praveṣṭavye dīpo yatnena dhāryatām

Our plain-language meaning of this verse is waiting for scholar review.