We receive mantras from gurus, not from books. It is irrelevant which book a mantra came in. One must chant the mantra that has been given to one by the guru, only then will one receive full benefit. We must also know the purpose for chanting this mantra, and that is fully explained in the Bhagavad Gita by Lord Krishna. Thus it is more relevant for the present times to study the Bhagavad Gita.
(i have not yet found out how to make quotations on this forum)
You are correct about your comments jndas-maharaj, but isnt Shri Krishna the Jagadguru, then why didnt he mention this mantra in the gita? If this is a foolish question please accept my appologies. The maha mantra isnt mentioned in the gita. If Shri Krishna is the jagadguru and purna avatara, then why is the name of Shri Rama neccesary?
Jaya Shri Devi
Winand