Lord Sri Krsna, the Supreme Personality of Godhead, is merciful, but His mercy does not depend on mundane rules and regulations. He is dependent only on affection and nothing else. Service to Lord Krsna can be rendered in two ways. One can serve the Lord in affection or in veneration. When service is rendered in affection, it is the Lord's special mercy. When service is rendered in veneration, it is doubtful whether Krsna's mercy is actually involved. If Krsna's mercy is there, it is not dependent on any prescribed caste or creed. Sri Caitanya Mahaprabhu wanted to inform Sarvabhauma Bhattacarya that Lord Krsna is the spiritual master of everyone, and He does not care for mundane caste or creed. Therefore Sri Caitanya Mahaprabhu cited the example of Lord Krsna's accepting food at the house of Vidura, who was a sudra by birth. By the same token, Isvara Puri, an empowered spiritual master, could show mercy to anyone. As such, he accepted Govinda, although the boy was born in a sudra family. When Govinda was initiated, he became a brahmana and was accepted as Isvara Puri's personal servant. In the Hari-bhakti-vilasa, Sri Sanatana Gosvami states that one who is initiated by a bona fide spiritual master immediately becomes a brahmana. A pseudo spiritual master cannot transform a person into a brahmana, but an authorized spiritual master can do so. This is the verdict of sastra, Sri Caitanya Mahaprabhu and all the Gosvamis.