Obviously life is full of offense. We can't legislate good taste or make everything that offends everyone illegal. Freedom of speech entails the freedom to offend. But that doesn't mean we have to offend.
Few governments have any kinds of laws clearly governing the limits of speech and of anonymity online. Standards are being set piecemeal by corporations, which are accountable to no one but their shareholders.
On a regular basis, I do something that most people in the free world do -- I ask my friends their opinion on something: politics, religion, sports, a concert...and I take for granted the fact that this is OK.
While certain religious views may not always be acceptable to the majority, they must be vigorously defended, not just because of the moral imperative to protect free speech, but also because to do otherwise would open the doors for further restrictions.