Srimad Bhagavatam Canto 12, Chapter 08, Text 35

SB 12.8.35

te vai bhagavato rupe
 nara-narayanav rsi
drstvotthayadarenoccair
 nanamangena danda-vat
 
Translation: 
 
These two sages, Nara and Narayana, were the direct personal forms of the Supreme Lord. When Markandeya Rsi saw Them, he immediately stood up and then with great respect offered Them obeisances by falling down flat on the ground like a stick.
Srimad Bhagavatam Canto 12, Chapter 08, Text 33-34
Srimad Bhagavatam Canto 12, Chapter 08, Text 36