Material Energy: Maya or Nescience

                                                                  Q: Sastra says guru is the representative of Lord Krishna and we should not see him as an ordinary man. At the same time we read that also great personalities can fall down from the position of guru (SB 5.18.4 p and Adi-lila 7.110 p).
                                                                  So my question is how do we are supposed to see the guru? How can we reconcile both statements? It seems very difficult to me to worship my guru as the representative of Krishna and at the same time thinking he can fall down from his position.

                                                                  Q. 1. I have a question about nescience. I understand what the word means but I do not understand it in the context that it is used in His Divine Graces books. If you think I might understand could you give me the mercy of some explanation.