Matsyapurana 40.17

40.17

atha lokamimaṃ jitvā lokaṃ cāpi jayetparam
āsyena tu yadāhāraṃ govanmṛgayate muniḥ
athāsya lokaiḥ sarvo yaḥ so 'mṛtatvāya kalpate //

One whose plethora of flesh and blood has disappeared by his severe penances and who has thereby become reduced to a mere skeleton, showing all his decayed bones, and devoid of the feeling of prosperity or adversity, sticks to his meditation, is said to be firm in his vow of silence (muni). When such a sage chews his morsel like a cow, and remains silent like the latter, he wins both the worlds and paves his way for the final bliss.—16-17.