Q-It seems like a contradiction—that in one place it says that the highest service is service to the spiritual master and in another place, it seems as though serving Krishna is higher.
A- There is no contradiction, if the spiritual master is one who is always connected to Krishna's service. Serving the spiritual master is serving Krishna. It depends upon the spiritual master's transparency. In the material world, it is the duty of the spiritual master to awaken this service-attitude and to train the disciple in this service-attitude toward the Lord. It begins by giving relevant instructions for the disciple's progressive advancement in spiritual life. By following these instructions, the disciple qualifies himself for Krishna's service. Therefore, serving the spiritual master is essential to become qualified to serve Krishna. Ultimately we are all servants of Krishna, and everyone has a service according to their particular relationship with Krishna
MKV, Vol 2- Pg 15, (Q/A Meeting With Disciples, Divnomorsk—6/10/01)