Answer:
One main limit is "Social Harmony".
Your speech is not responsible for any Riots or create a tensions in social life of country. Your speech did not hurt any religious group.That may affect nation's social,economical life. That would not acceptable as morally. as we are Human being so we have to do pay duties for Humanity and rest else thing.That minimum expectation by each national constitution. If you wants a focus on some religiosity points then conduct the debate on same points, for that take permission of government. If government is not able to give permission to you then check your constitution, as per constitution take permission of your Han able court and If court is not going to gave permission to you for this then two points in focus
1. your request is not with laws.
2.In your request may follow the laws (morally) but system like(Pakistan) not agree with you cause of extremist's pressure.
In First case you activities is in arena of crimes, and Second case you have to fight with current system for saving Humanity.
One key point while fighting with system is you have to invoke the peoples then government is allows to make changes. But this is the not easy way.