Now I come to the last part of this creed--the doctrine of eternal punishment. I have concluded that I will never deliver a lecture in which I will not attack the doctrine of eternal pain. That part of the Congregational creed would disgrace the lowest savage that crouches and crawls in the jungles of Africa. The man who now, in the nineteenth century, preaches the doctrine of eternal punishment, the doctrine of an eternal hell, has lived in vain. Think of that doctrine! The eternity of punishment! I find in this same creed--in this latest utterance of Congregationalism--that Christ is finally going to triumph in this world and establish his kingdom. This creed declares that "we believe in the ultimate prevalence of the kingdom of God over all the earth." If their doctrine is true he will never triumph in the other world. The Congregational Church does not believe in the ultimate prevalence of the kingdom of Christ in the world to come. There he is to meet with eternal failure. He will have billions in hell forever.

In this world we never will be perfectly civilized as long as a gallows casts its shadow upon the earth. As long as there is a penitentiary, within the walls of which a human being is immured, we are not a perfectly civilized people. We shall never be perfectly civilized until we do away with crime. And yet, according to this Christian religion, God is to have an eternal penitentiary; he is to be an everlasting jailer an everlasting turnkey, a warden of an infinite dungeon. and he is going to keep prisoners there forever, not for the purpose of reforming them--because they are never going to get any better, only worse--but for the purpose of purposeless punishment. And for what? For something they failed to believe in this world. Born in ignorance, supported by poverty, caught in the snares of temptation, deformed by toil, stupefied by want--and yet held responsible through the countless ages of eternity! No man can think of a greater horror; no man can dream of a greater absurdity. For the growth of that doctrine ignorance was soil and fear was rain. It came from the fanged mouths of serpents, and yet it is called "glad tidings of great joy.

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The doctrine of eternal pain is my trouble with this Christian religion. I reject it on account of its infinite heartlessness. I cannot tell them too often, that during our last war Christians, who knew that if they were shot they would go right to heaven, went and hired wicked men to take their places, perfectly willing that these men should go to hell provided they could stay at home. You see they are not honest in it, or they do not believe it, or as the people say, "they don't sense it." They have not imagination enough to conceive what it is they believe, and what a terrific falsehood they assert. And I beg of every one who hears me to-night, I beg, I implore, I beseech you, never to give another dollar to build a church in which that lie is preached. Never give another cent to send a missionary with his mouth stuffed with that falsehood to a foreign land. Why, they say, the heathen will go to heaven, any way, if you let them alone. What is the use of sending them to hell by enlightening them? Let them alone. The idea of going and telling a man a thing that if he does not believe, he will be damned, when the chances are ten to one that he will not believe it, is monstrous. Do not tell him here, and as quick as he gets to the other world and finds it is necessary to believe, he can say "Yes." Give him a chance.

http://www.sacred-texts.com/aor/ing/vol02/i0165.htm