Srimad Bhagavatam Canto 11, Chapter 29, Text 16

SB 11.29.16

visrjya smayamanan svan
 drsam vridam ca daihikim
pranamed danda-vad bhumav
 a-sva-candala-go-kharam
 
Translation: 
 
Disregarding the ridicule of one’s companions, one should give up the bodily conception and its accompanying embarrassment. One should offer obeisances before all — even the dogs, outcastes, cows and asses — falling flat upon the ground like a rod.
 
Purport: 
 
One should practice seeing the Supreme Personality of Godhead within all creatures. Sri Caitanya Mahaprabhu advised all devotees to consider themselves lower than a blade of grass and to be more tolerant than a tree. In such a humble position, one will not be disturbed in the prosecution of pure devotional service to the Lord. A devotee does not foolishly think that a cow or an ass is God, but rather the devotee sees the Supreme Lord within all creatures, and on this higher, spiritual plane he does not discriminate.
Srimad Bhagavatam Canto 11, Chapter 29, Text 15
Srimad Bhagavatam Canto 11, Chapter 29, Text 17