"The answer to your question is this: Unless one is a resident of Krishna Loka, one can not be a Spiritual Master. That is the first proposition. A common person, a mediocre, cannot be a Spiritual Master, and if he does, he would only create disturbances. And who is a liberated person? One who knows Krishna. It is established in the Bhagavad-gītā, chapter four, that anyone who knows Krishna truly is immediately liberated and, after leaving his current body, goes directly to Krishna. This means that he becomes a resident of Krishna Loka. As soon as one is liberated, he immediately becomes a resident of Krishna Loka, and anyone who knows the truth about Krishna can become a Spiritual Master. That is Lord Caitanya's teaching. In summary,