For the secret of man's being is not only to live but to have something to live for. Without a stable conception of the object of life, man would not consent to go on living, and would rather destroy himself than remain on earth, though he had bread in abundance.
The comprehensibility of the world seems to me a wonder or eternal secret. Here lies the sense of wonder which increases even more with the development of our knowledge.
Tremendous purity, tremendous renunciation, is the one secret of spirituality. “Neither through wealth, nor through progeny, but through renunciation alone is immortality to be reached,” say the Vedas. “Sell all that thou hast and give to poor, and follow me,” says the Christ. So all great saints and prophets have expressed it, and have carried it out in their lives. How can great spirituality come without renunciation?
Muhammad has always been standing higher than the Christianity. He does not consider god as a human being and never makes himself equal to God. Muslims worship nothing except God and Muhammad is his Messenger. There is no any mystery and secret in it.
We have all our private terrors, our particular shadows, our secret fears. We are afraid in a fear which we cannot face, which none understands, and our hearts are torn from us, our brains unskinned like the layers of an onion, ourselves the last.