The soul of the world: the One. Everything we see, we feel, real and unreal, our consciousness our soul, they are all one and the purpose of our lives is to be one with the One. This is the message which I feel the author wants to give. This concept is very interesting as it can be related to the Indian Philosophy, where the One, the Spirit Supreme, is the Brahman.
Brahman is pure Consciousness, pure Love. It is this exactly what Coelho wants to say, that the language of the world lies in Pure Love. Pure Love is pure joy, is creation and is infinite.
“My heart is afraid that it will have to suffer,” the boy confides to the alchemist one night as they look up at a moonless night. “Tell your heart that the fear of suffering is worse than the suffering itself” said the alchemist. – (Alchemist)