Americans place a high value on free speech. However, they seldom recognize that the American idea of free speech actually contains two completely separate ideas.
One of these ideas is that there should be a free flow of information so that people can have access to relevant data in deciding what to believe and what to do. While there may be good reasons to restrict the flow of information in certain very limited situations (such as a nation trying to implement a secret strategy during a war), most of the time I think there ought to be a free flow of information. Particularly, I think there ought to be a free flow of information when it comes to data necessary to accurately understand the world we live in, especially data relating to fundamental matters of theoretical and practical importance--data flowing from religious, philosophical, and scientific sources.
The other idea involved in the American concept of "free speech" is that people should be free to publicly say whatever they want, no matter how offensive, mean-spirited, and useless it may be. For example, I just read an article this morning in the Salt Lake Tribune (http://www.sltrib.com/sltrib/news/54667613-78/language-ogden-ordinance-lowder.html.csp) talking about how the city of Ogden is considering passing a ban on obscene outbursts in public parks. "Brian Barnard, a civil rights attorney in Salt Lake City, had two words for it: 'Clearly unconstitutional.'" In other words, it violates the right of free speech. According to Barnard, and to most Americans, being able to make stupid, worthless, obscene comments in public parks is a fundamental human right.
I see no reason why speech such as this should be protected by law. Rather, I think it should not be. Biblical civil law has a prohibition of blasphemy (Leviticus 24:10-15). Biblical law also condemns cursing of one's parents and other authorities, and prescribes death for such cursing (Leviticus 20:9; Exodus 22:28; 1 Kings 2:8-9). The Bible teaches that we are to show respect for our elders (Leviticus 19:32). To premeditatively and publicly curse another human being, made in the image of God, is blasphemous. I think the general equity of biblical civil law would require civil punishment for such behavior. Although America has a hard time with this concept, European nations seem to find it more natural, as can be seen in the prevalence of "hate speech" laws (http://en.wikipedia.org/wiki/Hate_speech - not that I am defending all the particulars of these laws; I am simply pointing out that they reflect the sense, also echoed in biblical law, that the dignity and honor of human beings ought to be in some way protected by law from defamation).
American arguments in defense of allowing obscene and defamatory public speech (let's call this free speech #2, or FS2) are often based in the aforementioned confused mingling of FS2 with the other idea of free speech, the idea that there should normally be a free flow of information/data on important topics (we'll call this free speech #1, or FS1). So Americans often say, for example, that we have to allow people the freedom to publicly insult and defame people in public parks because, if we didn't, we would be stopping people from thinking for themselves, from coming to their own conclusions, and we would be imposing a rigid, unquestioned ideology on people. But once we separate FS1 and FS2, we see what a nonsensical argument this is. Sure, I need to be able to have access to all the relevant data when I am trying to decide what the true religion is, or when I am thinking through some difficult philosophical issue, or when I am trying to use science to develop new medical cures. But none of this is helped by allowing people to blurt out obscenities in public parks in Ogden. Nor would it be hindered if such obscene speech became forbidden.
This confusion between FS1 and FS2 is prominent in certain secular attacks on biblical law. Secularists often argue that biblical civil law would impose a thought-straightjacket on people, preventing them from thinking for themselves in important matters and withholding from them all the relevant evidence. "Laws against blasphemy and the public advocacy of non-biblical religion would prevent people from hearing evidence against the preferred religion of the government, and it would cause people to grow intellectually weak as they are not allowed to consider alternative viewpoints!" But biblical prohibitions against the public defamation of God, of rulers, and of fellow human beings, does not at all imply that people should not be allowed to be aware of and to think through arguments against Christianity. There is no biblical prohibition on allowing people to, say, read about commonly-made atheist arguments, or to discuss them, or to learn about what prominent proponents of false worldviews elsewhere in the world might be saying. What is forbidden is not the dissemination of data/information/arguments, but the public promotion and practice of false religious views and blasphemous and defamatory speech. So, in a society that follows biblical law, I could have access to and read The God Delusion by Richard Dawkins. I could think as long as I wish upon the arguments he makes in the book. What I could not do is go out and publicly promote atheism, or stand on the street corners spouting out blasphemous insults against God. Prohibitions on blasphemy and the promotion of false religion will keep the public sphere clear of disruptive and offensive filth, but it will not hinder anyone's intellectual development or ability to think freely and thoroughly. In fact, as honesty and the ability to "give an answer for the hope that is in you" are important biblical values, I would argue that the citizens of a biblical society ought to be well-trained in understanding other people's points of view, so that they will not be ignorant of the false ideas and bad arguments that circulate in the world, and so that they will be trained to avoid such errors by the right use of well-developed critical thinking skills.
Of course, as with many secularist arguments, this argument against biblical law is used somewhat inconsistently, in that secular societies also have laws prohibiting certain ideas from being promoted and acted upon. For example, what would happen to me if I went out on the street corner and began to promote Al Qaeda? Do you think I would be left alone by law enforcement? Of course not. And if I were to protest their interference, saying, "This is a country of free speech! We need to be able to think for ourselves, so no views should be hindered from being promoted!" I doubt this would have much effect. The response would be that I do not have the freedom to advocate things that are harmful to the fundamental values the society ought to protect. That makes sense. All societies prohibit such advocacy. America allows profane and blasphemous speech not because it is "nicer" or "freer" than a biblical society would be, but because modern American culture, being Agnostic, doesn't care about the public honor of God (or apparently even the public honor and dignity of its citizens). A biblical society, on the other hand, would put a high value on the public honor of God and the dignity of rulers and of other human beings, and this would be reflected in its laws.