By patriotism is meant, not only spontaneous, instinctive love for one's own nation, and preference for it above all other nations, but also the belief that such love and preference are good and useful.
I am a Hindu by birth. And yet I do not know much of Hinduism, and I know less of other religions. In fact I do not know where I am, and what is and what should be my belief. I intend to make a careful study of my own religion and, as far as I can, of others.
A Sannyasin cannot belong to any religion, for his is a life of independent thought, which draws from all religions; his is a life of realisation, not merely of theory or belief, much less of dogma.