Mahabharata 9.51.6

उपवासैः पूजयन्ती पितॄन्देवांश्च सा पुरातस्यास्तु तपसोग्रेण महान्कालोऽत्यगान्नृप

upavāsaiḥ pūjayantī pitṝndevāṃśca sā purātasyāstu tapasogreṇa mahānkālo'tyagānnṛpa

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