Vaishnava Samhita. Narasimha Mehta Charitam I. Vol III Book VI Chp 15 Shloka 1

श्रीसद्गुरुरुवाच 

आसीद्भक्तजनश्रेष्टो नरसिह्म इति श्रुतः  |
वक्ष्यामि तस्य चरितं कृष्णभक्तिप्रदं शुभम्  ||

Shri Sadguru said

There was a great bhakta named Narasimha Mehta. Now I am going to narrate his story that blesses the listener with devotion to Shri Krishna.