Srimad Bhagavatam Canto 06, Chapter 07, Text 32

SB 6.7.32

vrnimahe tvopadhyayam
 brahmistham brahmanam gurum
yathañjasa vijesyamah
 sapatnams tava tejasa
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
Since you are completely aware of the Supreme Brahman, you are a perfect brahmana, and therefore you are the spiritual master of all orders of life. We accept you as our spiritual master and director so that by the power of your austerity we may easily defeat the enemies who have conquered us.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
One must approach a particular type of guru to execute a particular type of duty. Therefore although Visvarupa was inferior to the demigods, the demigods accepted him as their guru to conquer the demons.
Srimad Bhagavatam Canto 06, Chapter 07, Text 31
Srimad Bhagavatam Canto 06, Chapter 07, Text 33