The most dangerous madmen are those created by religion, and... people whose aim is to disrupt society always know how to make good use of them on occasion.
There is not a Musselman[Muslim] alive who would not imagine that he was performing an action pleasing to God and his Holy Prophet by exterminating every Christian on earth, while the Christians are scarcely more tolerant on their side.
Mankind have banned the Divinity from their presence; they have relegated him to a sanctuary; the walls of the temple restrict his view; he does not exist outside of it.
Only a very bad theologian would confuse the certainty that follows revelation with the truths that are revealed. They are entirely different things.
Disturbances in society are never more fearful than when those who are stirring up the trouble can use the pretext of religion to mask their true designs.
Bad company is as instructive as licentiousness. One makes up for the loss of one's innocence with the loss of one's prejudices.
A thing is not proved just because no one has ever questioned it. What has never been gone into impartially has never been properly gone into. Hence scepticism is the first step toward truth. It must be applied generally, because it is the touchstone.