In light of some recent discussion, I think it is time to specify some basic propositions.
(1) There is no God.
Some people may be distressed by this fact. However, I am under no obligation to bury the truth simply because someone cannot handle the truth. In order for people to best fulfill the most and strongest of their desires, given the fact that they act to fulfill the most and strongest of their desires given their beliefs, they need true beliefs. Belief that a God exists is not on the list.
Even if there is a God, we know nothing about its qualities. It could be a childish God who created the earth and its occupants at set us to war against each other for its own amusement. Or it could be a bored God concerned with something else in some other part of the universe where we are an unforeseen side-effect that God cares nothing about. Or it could be a God who is more impressed with the human who uses its brain and available evidence to conclude that it does not exist than with those who shamelessly assert that faith is a virtue. All claims about what God is like have to be justified separately from the proposition that a God exists.
(2) Belief that a God exists is not morally objectionable.
We all have false beliefs. None of us have time to hold all of our beliefs up to the light of reason and sort them all out, so we all have unfounded false beliefs.
Consider a person with no beliefs. How does he hold that first belief up to the light of reason to judge whether to accept it or not? He cannot. Our first beliefs are acquired arationally. Later beliefs are evaluated in part based on their coherence with these early arational beliefs. They help to select subsequent beliefs. It is a method prone to error. If people are to be held in moral contempt for every false belief they adopt, then we must hold everybody - even ourselves - in moral contempt.
(3) People who base behavior harmful to the interests on others on scripture are evil.
If you are going to do something harmful to the interests of others - if you are going to do anything that has a reasonable chance of harming the interests of others - you have a moral obligation to provide good reason to do so. You have an obligation to begin with the assumption that others are not to be harmed unless the value of doing harm is proved beyond a reasonable doubt, and to provide that reason.
Religious texts offer no good reason whatsoever for behavior harmful to others.
As soon as somebody quotes scripture in defense of a law or policy that is potentially harmful to the interests of others, that person has done what no good person would do. that person has violated the moral prescription against doing harm without good reason.
Religious beliefs are fine for people who apply them to their own lives. If you want to use scripture to decide what to eat, when to eat, what to wear, when to work, when to refrain from working, and the like, you are free to do so. Just as you are free to base these decisions on your horoscope, tea leaves, tarot cards, or the role of a die, if that pleases you.
However, if your scripture tells you to do harm to your neighbor, your act is no more justified than that of the person who looks at his horoscope, reads, "CANCER: Your neighbor must die today. Do anything in your power to make sure that he does not survive to see another dawn."
Killing your neighbor and appealing to scripture makes you a murderer. This includes those who support capital punishment who quote scripture that calls for "an eye for an eye." They are murderers, because they have killed without providing good reason to kill. They are murderers for the same reason the person reading the horoscope above and acting on it would be a murderer.
Maiming your neighbor and appealing to scripture makes you guilty of malicious assault. Taking your neighbor's property and appealing to scripture makes you a thief. This applies to anybody fighting over land where they base their fight on the claim, "God gave this land to us." You are thieves. And if you kill others whole engage in an act of theft then you are guilty of murder here as well.
The instant a person appeals to scripture to justify harm to others, at that instant they have done evil. Even if the person harmed actually deserves to be harmed - even if they are actually guilty, the person who has appealed to scripture to justify doing harm has still committed an evil act. This is because it is still the duty of every human being to presume that others are not to be harmed and to use only good reasons to show that they should be harmed.
Again, it is just like the horoscope case. Even if the neighbor turns out to be somebody who deserves to be killed, the fact that the killer did not have good reason to do so makes the killer a murderer.
Yes, this means that there are a lot of people around the world patting themselves on the back and puffing out their chests with pride over how great they are because they are fighting God's war should be ashamed of themselves. Their arrogant false pride is wholly undeserved. For the sake of their victims - those to whom they do harm without justification - it is not only permissible, it is obligatory to stick a pin in that inflated sense of pride and tell these people what type of people they really are.
The Christian conservative who looks to scripture and finds justification for banning gay marriage is guilty of the same moral crime as the Muslim who looks to scripture and finds justifiation for flying an airplane into a skyscraper.
If your reasons are not the type of reasons that are admissible in court, then they are not the types of reasons that should be permissible in Congress.
However, this applies ONLY to those who appeal to scripture to justify harmful actions. As I have argued, a rancher who gets drunk and drives around his ranch - where there are no other people to hit - is NOT guilty of any type of moral negligence, because he does not put others at risk. Similarly, people are free to be as intellectually reckless as they wish with beliefs that do not threaten others. It is when people put others at risk that they acquire the obligation to act (and to think) more responsibly. It is when they consider policies harmful to others that they become evil if they seek justification for those harms in scripture.
So, if we are going to condemn people, the people who deserve our condemnation are not "the religious". It is "the people who base behavior potentially harmful to others without good reason" - a group both broader and narrower than "the religious" and likely includes a good number of atheists as well.
If a person commits an act of attempting to justify behavior harmful to others by means of appeal to scripture, then this makes that person a member of the group, "People who have attempted to justify behavior harmful to others without good reason" - all of whom have done something evil and can justly be labeled as such.
This is true in the same way that a person who commits rape becomes a member of the group, "Rapists", all of whom have done something evil. And anybody who commits theft becomes a member of the group "thieves", all of whom have done something evil. There is no bigotry involved in labeling these groups what they are or to say that they all deserve condemnation based on that fact.
But nothing in this - nothing at all - justifies extending condemnation to anybody outside of the group, "rapists", "thieves", and "those who seek to justify behavior harmful to others without good reason."