After all these responses my learning is this. It is not proper to place titles such as Mr or Prof in front of first names of  English speaking persons.

 

In fact I did not do that. The thumb rule I knew was put these titles in front of second names when you want to be respectful. Use the first name if you want to be informal. But I never thought about  what could be the cultural connotation if title is put in front of first name. Now it seems that it evokes feelings of strangeness, insult, offense etc.

 

It was strange to me when elderly scholars asked me to call them by their first name. I was not able to do that at all. I was strongly inhibited from my deep inside from doing that.  I saw very young boys address Prof. Wendy Doniger as Wendy or Prof. Mckim Marriott as Kim. To my sensibility that sounded as weird, not a good practice. I was able to address Prof. Yigal Bronner as Yigal. Probably because he was young. I wanted to know if my addressing persons as Prof. Doniger or Prof. Marriott was offensive. I was told that it was not.  

 

Now, this is a new point I learnt.  

  

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