Mahabharata 14.17.26

तमसा संवृतज्ञानः संवृतेष्वथ मर्मसुस जीवो निरधिष्ठानश्चाव्यते मातरिश्वना

tamasā saṃvṛtajñānaḥ saṃvṛteṣvatha marmasusa jīvo niradhiṣṭhānaścāvyate mātariśvanā

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