If the Pentateuch be true, religious persecution is a duty. The dungeons of the Inquisition were temples, and the clank of every chain upon the limbs of heresy was music in the ear of God. If the Pentateuch was inspired, every heretic should be destroyed; and every man who advocates a fact inconsistent with the sacred book, should be consumed by sword and flame.In the Old Testament no one is told to reason with a heretic, and not one word is said about relying upon argument, upon education, nor upon intellectual development—nothing except simple brute force. Is there to-day a christian who will say that four thousand years ago, it was the duty of a husband to kill his wife if she differed with him upon the subject of religion? Is there one who will now say that, under such circumstances, the wife ought to have been killed? Why should God be so jealous of the wooden idols of the heathen? Could he not compete with Baal? Was he envious of the success of the Egyptian magicians? Was it not possible for him to make such a convincing display of his power as to silence forever the voice of unbelief? Did this God have to resort to force to make converts? Was he so ignorant of the structure of the human mind as to believe all honest doubt a crime? If he wished to do away with the idolatry of the Canaanites, why did he not appear to them? Why did he not give them the tables of the law? Why did he only make known his will to a few wandering savages in the desert of Sinai? Will some theologian have the kindness to answer these questions? Will some minister, who now believes in religious liberty, and eloquently denounces the intolerance of Catholicism, explain these things; will he tell us why he worships an intolerant God? Is a god who will burn a soul forever in another world, better than a christian who burns the body for a few hours in this? Is there no intellectual liberty in heaven? Do the angels all discuss questions on the same side? Are all the investigators in perdition? Will the penitent thief, winged and crowned, laugh at the honest folks in hell? Will the agony of the damned increase or decrease the happiness of God? Will there be, in the universe, an eternal auto da fe?

~ Robert G. Ingersoll

It is my conviction that, with the spread of true scientific culture, whatever may be the medium, historical, philological, philosophical, or physical, through which that culture is conveyed, and with its necessary concomitant, a constant elevation of the standard of veracity, the end of the evolution of theology will be like its beginning—it will cease to have any relation to ethics. I suppose that, so long as the human mind exists, it will not escape its deep-seated instinct to personify its intellectual conceptions. The science of the present day is as full of this particular form of intellectual shadow-worship as is the nescience of ignorant ages. The difference is that the philosopher who is worthy of the name knows that his personified hypotheses, such as law, and force, and ether, and the like, are merely useful symbols, while the ignorant and the careless take them for adequate expressions of reality. So, it may be, that the majority of mankind may find the practice of morality made easier by the use of theological symbols. And unless these are converted from symbols into idols, I do not see that science has anything to say to the practice, except to give an occasional warning of its dangers. But, when such symbols are dealt with as real existences, I think the highest duty which is laid upon men of science is to show that these dogmatic idols have no greater value than the fabrications of men's hands, the stocks and the stones, which they have replaced.

~ Thomas Henry Huxley