Srimad Bhagavatam Canto 07, Chapter 15, Text 73

SB 7.15.73

tavad dasyam aham jajñe
 tatrapi brahma-vadinam
susrusayanusangena
 prapto ’ham brahma-putratam
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
Although I took birth as a sudra from the womb of a maidservant, I engaged in the service of Vaisnavas who were well-versed in Vedic knowledge. Consequently, in this life I got the opportunity to take birth as the son of Lord Brahma.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
The Supreme Personality of Godhead says in Bhagavad-gita (9.32):
 
mam hi partha vyapasritya
 ye ’pi syuh papa-yonayah
striyo vaisyas tatha sudras
 te ’pi yanti param gatim
 
“O son of Prtha, those who take shelter in Me, though they be of lower birth — women, vaisyas [merchants], as well as sudras [workers] — can approach the supreme destination.” It doesn’t matter whether a person is born as a sudra, a woman or a vaisya; if he associates with devotees repeatedly or always (sadhu-sangena), he can be elevated to the highest perfection. Narada Muni is explaining this in relation to his own life. The sankirtana movement is important, for regardless of whether one is a sudra, vaisya, mleccha, yavana or whatever, if one associates with a pure devotee, follows his instructions and serves the pure devotee, his life is successful. This is bhakti. Anukulyena krsnanusilanam. Bhakti consists of serving Krsna and His devotees very favorably. Anyabhilasita-sunyam. If one has no desire other than to serve Krsna and His devotee, then his life is successful. This is explained by Narada Muni through this practical example from his own life.
Srimad Bhagavatam Canto 07, Chapter 15, Text 72
Srimad Bhagavatam Canto 07, Chapter 15, Text 74