The language of the soul is one, the languages of nations are many; their customs and methods of life are widely different. Religion is of the soul and finds expression through various nations, languages, and customs. Hence it follows that the difference between the religions of the world is one of expression and not of substance; and their points of similarity and unity are of the soul, are intrinsic, as the language of the soul is one, in whatever peoples and under whatever circumstances it manifests itself. The same sweet harmony is vibrant there also, as it is on many and diverse instruments.
– Swami Vivekananda