I know it would be sinful to be uncharitable towards any other person, regardless of their beliefs. However, what specific teachings state that we must respect other people’s beliefs? E.g. The film on Muhammud was disrespectful in my opinion and it makes me wonder has the Church has ever adressed such issues, either in it’s writings or public speeches?
What is the universal definition of the respect of the other religions in the catholicism (catholic definition)?
In general, as catholic, we have to respect the human nature, I mean the human gender, male and female, and each person (personalist approach) in the respect of the natural moral law of human beings (human dignity and her corollaries).
Otherwise, concerning the religious doctrines, the religious beliefs, the religious mentalities, the religious practices, the religious reasonnings, the religious explainations in many domains (moral, philosophical, theological, political, judicial, juridical, economical, medical, psychological, social, educational, instructional,… and even religious) , we have the right, and sometimes we have the moral duty and the moral obligation to denounce by the speech and the teaching if:
the moral natural law of human being is attacked by this doctrines, this beliefs, this mentalities, this practices, this reasonnings, this explainations…etc.
Thus, as catholic we cannot respect,
in thought, (interior thinking) a wrong doctrine, a wrong belief, a wrong mentality, a wrong practice, a wrong reasonning, a wrong explanation, a wrong intellectual approach, a wrong heresy or an wrong ideology who is going against the natural moral law of the humanity.
The moral obligation for each catholic and for each other human being is to make the difference between the person and the acts (in largo sensu), and to react differently in function of the nature of wrong doctrine…, in function of the degree of the denaturation of this wrong doctrine…, in the respect of the human dignity of each one.
We have the list of heresies, of ideologies with their corollaries that are denounced by the Roman Catholic Church.
About the unchristian religions, we have to respect only the part of the natural law that is inside of those religions. .
The phenomenom of syncretism is wrong and very against the catholic moral, be careful is a nice slogan.
The reaction has to be prudent, moderated, fair (the proportionality) and not absurd., objective and realistic.
The difference is between the exterior acts and the thoughts, but the expression of thinking has to be free, by principle.
) is that I see people who somehow arrived at the same core values I hold, of helping others, loving others, being charitable in thought and deed. I know Catholics, sadly, who gossip, swear, yell, and criticize others endlessly. (And these are Catholics who say the daily Rosary and go to daily Mass. 
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