“In short, every virtue has been a crime, and every crime a virtue. The church has burned honesty and rewarded hypocrisy. And all this, because it was commanded by a book — a book that men had been taught implicitly to believe, long before they knew one word that was in it. They had been taught that to doubt the truth of this book — to examine it, even — was a crime of such enormity that it could not be forgiven, either in this world or in the next.”

Heretics and Heresies (1874)
Context: Nature never prompted a loving mother to throw her child into the Ganges. Nature never prompted men to exterminate each other for a difference of opinion concerning the baptism of infants. These crimes have been produced by religions filled with all that is illogical, cruel and hideous. These religions were produced for the most part by ignorance, tyranny and hypocrisy. Under the impression that the infinite ruler and creator of the universe had commanded the destruction of heretics and infidels, the church perpetrated all these crimes:
Men and women have been burned for thinking there is but one God; that there was none; that the Holy Ghost is younger than God; that God was somewhat older than his son; for insisting that good works will save a man without faith; that faith will do without good works; for declaring that a sweet babe will not be burned eternally, because its parents failed to have its head wet by a priest; for speaking of God as though he had a nose; for denying that Christ was his own father; for contending that three persons, rightly added together, make more than one; for believing in purgatory; for denying the reality of hell; for pretending that priests can forgive sins; for preaching that God is an essence; for denying that witches rode through the air on sticks; for doubting the total depravity of the human heart; for laughing at irresistible grace, predestination and particular redemption; for denying that good bread could be made of the body of a dead man; for pretending that the pope was not managing this world for God, and in the place of God; for disputing the efficacy of a vicarious atonement; for thinking the Virgin Mary was born like other people; for thinking that a man's rib was hardly sufficient to make a good-sized woman; for denying that God used his finger for a pen; for asserting that prayers are not answered, that diseases are not sent to punish unbelief; for denying the authority of the Bible; for having a Bible in their possession; for attending mass, and for refusing to attend; for wearing a surplice; for carrying a cross, and for refusing; for being a Catholic, and for being a Protestant; for being an Episcopalian, a Presbyterian, a Baptist, and for being a Quaker. In short, every virtue has been a crime, and every crime a virtue. The church has burned honesty and rewarded hypocrisy. And all this, because it was commanded by a book — a book that men had been taught implicitly to believe, long before they knew one word that was in it. They had been taught that to doubt the truth of this book — to examine it, even — was a crime of such enormity that it could not be forgiven, either in this world or in the next.