Srimad-Bhagavatam: Canto 12 - Chapter 1 - Verse 35
Sanskrit:
ते वै भगवतो रूपे नरनारायणावृषी ।दृष्ट्वोत्थायादरेणोच्चैर्ननामाङ्गेन दण्डवत् ॥ ३५ ॥
ITRANS:
te vai bhagavato rūpenara-nārāyaṇāv ṛṣīdṛṣṭvotthāyādareṇoccairnanāmāṅgena daṇḍa-vat
Translation:
These two sages, Nara and Nārāyaṇa, were the direct personal forms of the Supreme Lord. When Mārkaṇḍeya Ṛṣi saw Them, he immediately stood up and then with great respect offered Them obeisances by falling down flat on the ground like a stick.