Vaishnava Samhita. Raskhan Charitam. Vol III Book VII Chp 13 Shlokas 1 - 2

श्रीसद्गुरुरुवाच

म्लेच्छःकिरातो यवनश्चण्डालः पुल्कसोपि वा |

साधुसङ्गममात्रेण लोकपूज्या भवन्ति ते ||

जातिं न पृच्छेद्भक्तस्य केवलं वौष्णवः स्मृतः |

नीचोपि जन्मना मर्त्यौ हरिभक्त्या विशुद्धयति ||

Shri Sadguru said

Even a mleccha, a kirata, a yavana, or a chandala becomes worthy of veneration due to the association of the sandhus. One should not enquire a bhakta of his caste. For, any person who is blessed with Vishnu bhakti becomes a vaishnava irrespective of his birth. Even a low-born gets purified by Hari bhakti.