All speech should be protected except for speech that directly incites violence.
The rule in law is that the given speech must leave time for rebuttal. If someone says so and so is scum now let's go kill them; that would be inciting violence. There is no time for rebuttal. If someone says so and so is scum and he should be killed then that is protected I believe. It leaves time for rebuttal. It does not call for immediate action. So clearly religious hate speech leaves ample time for rebuttal.