Do you understand the meaning of " Mohammed is last prophet". It is that the god teaches his desciple untill he merges in God. So when one becomes devoid of (Moh n mad=Mohammed)there is no one to give u the message The atman is merged into god becomes one with God. Hence thereafter no messanger is required thus Prophet mohammed utters (Mohammed is the last messanger). One can only understand this if he is graced with the blessings of his Guru.
