A religion, even if it calls itself a religion of love, must be hard and unloving to those who do not belong to it.

The weak spot of religion is its ridiculousness

All Religions have this in common, that they are an outrage to common sense for they are pieced together out of a variety of elements, some of which seem so unworthy, sordid and at odds with man’s reason, that any strong and vigorous intelligence laughs at them; but others are so noble, illustrious, miraculous, and mysterious that the intellect can make no sense of them and finds them unpalatable. The human intellect is only capable of tackling mediocre subjects: it disdains petty subjects, and is startled by large ones. There is no reason to be surprised if it finds any religion hard to accept at first, for all are deficient in the mediocre and the commonplace, nor that it should require skill to induce belief. For the strong intellect laughs at religion, while the weak and superstitious mind marvels at it but is easily scandalized by it.

RELIGION: BECAUSE THINKING IS HARD.

I think that you are immune to the temptations of religion. If you are not, I cannot help you, any more than I could keep you from acquiring a drug habit. A religion is sometimes a source of happiness and I would not deprive anyone of happiness. But it is a comfort appropriate for the weak, not for the strong—and you are strong. The great trouble with religion—any religion—is that a religionist, having accepted certain propositions by faith, cannot thereafter judge those propositions by evidence. One may bask in at the warm fire of faith or choose to live in the bleak uncertainty of reason—but one cannot have both.

His Religion is not an easy one: with rigorous fasts, lavations, strict complex formulas, prayers five times a day, and abstinence from wine, it did not "succeed by being an easy religion." As if indeed any religion, or cause holding of religion, could succeed by that! It is a calumny on men to say that they are roused to heroic action by ease, hope of pleasure, recompense, — sugar-plums of any kind, in this world or the next! In the meanest mortal there lies something nobler.

The frustrating thing is that those who are attacking religion claim they are doing it in the name of tolerance, freedom and openmindedness. Question: Isn’t the real truth that they are intolerant of religion? They refuse to tolerate its importance in our lives.

Isn't all religions curious? If they weren't you wouldn't get anyone to believe them.

Religion isn't always pretty. Especially viewed from the outside, by an unbeliever.

The major religions on the Earth contradict each other left and right. You can't all be correct. And what if all of you are wrong? It's a possibility, you know. You must care about the truth, right? Well, the way to winnow through all the differing contentions is to be skeptical. I'm not any more skeptical about your religious beliefs than I am about every new scientific idea I hear about. But in my line of work, they're called hypotheses, not inspiration and not revelation.

I could go on, but the point is clear: religions make explicit claims about reality—about what exists and happens in the universe. These claims involve the existence of gods, the number of such gods (polytheism or monotheism), their character and behavior (usually loving and beneficent, but, in the case of Hindu and ancient Greek gods, sometimes mischievous or malevolent), how they interact with the world, whether or not there are souls or life after death, and, above all, how the deities wish us to behave—their moral code.
These are empirical claims, and although some may be hard to test, they must, like all claims about reality, be defended with a combination of evidence and reason. If we find no credible evidence, no good reasons to believe, then those claims should be disregarded, just as most of us ignore claims about ESP, astrology, and alien abduction. After all, beliefs important enough to affect you for eternity surely deserve the closest scrutiny.

Religion had never been a subject that interested Julia. She considered herself too smart to believe in things she had no evidence for, and that behaved in ways that violated every principle she’d ever observed or heard plausibly spoken about. And she considered herself too tough-minded to believe in things just because they made her feel better. Magic was one thing. With magic you were at least looking at reproducible results. But religion? That was about faith. Uneducated guesses made by weak minds.

We all know that any emotional bias — irrespective of truth or falsity — can be implanted by suggestion in the emotions of the young, hence the inherited traditions of an orthodox community are absolutely without evidential value.... If religion were true, its followers would not try to bludgeon their young into an artificial conformity; but would merely insist on their unbending quest for truth, irrespective of artificial backgrounds or practical consequences. With such an honest and inflexible openness to evidence, they could not fail to receive any real truth which might be manifesting itself around them. The fact that religionists do not follow this honourable course, but cheat at their game by invoking juvenile quasi-hypnosis, is enough to destroy their pretensions in my eyes even if their absurdity were not manifest in every other direction.

Organised religion is something I find hard to follow.