You have asked if it is true that the Spiritual Master remains in the material universe until all of His disciples are transferred to the Spiritual Sky. The answer is yes, this is the rule. Therefore, every student should be very much careful not to commit any offense which will be detrimental to this promotion to the Spiritual Kingdom, and thereby the Spiritual Master has to incarnate again to deliver him. This sort of mentality will be a kind of offense to the Spiritual Master. Out of the ten kinds of offenses, the number one offense is to disobey the orders of the Spiritual Master. The instructions given to the disciple by the Spiritual Master at the time of initiation should be strictly followed. That will make one advance to the spiritual path. But if one deliberately defies such instructions, then his advancement is hampered from the very beginning. This defying means to disconnect the relationship with the Spiritual Master. And anyone who defies and therefore disconnects the relationship with the Spiritual Master can hardly expect the assistance of the Spiritual Master life after life.

From Srila Prabhupada’s letter to Jayapataka — Los Angeles 11 July, 1969