Mahabharata 3.88.21

यच्च भूतं भविष्यच्च भवच्च पुरुषर्षभनारायणः प्रभुर्विष्णुः शाश्वतः पुरुषोत्तमः

yacca bhūtaṃ bhaviṣyacca bhavacca puruṣarṣabhanārāyaṇaḥ prabhurviṣṇuḥ śāśvataḥ puruṣottamaḥ

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