The Brotherhood of Religions

Because all the great truths of religion are common property, they do not belong exclusively to any one Faith. That is why nothing vital is gained by changing from one religion to another. You do not need to travel the whole world in order to find the water of truth. Is the above sentence on the universality of religious truths true in fact, or is it only verbiage? Four special lines of study may be followed in order to prove the fact is thus: common Symbols; common Doctrines; common Stories and common Morals.