ITA all the way with Wyliefan on this. And I don't know with why the discussion has drifted onto being concerned with other people's religions, because this particular comment is exclusively directed at christians.
Whether or not this particular person has a point, it's a valid concern for a religious leader to be concerned with what the people within his religion believe.
And it's also a part of the christian faith to be concerned with sharing it. It's not the case in all religions, but it's a core part of christianity.
Jesus instructed his disciples that way. Spreading the word is a strong idea throughout the new testament. I can't really see how that can be interpreted away.
BUT Jesus also said that in villages where the disciples and their message were not welcome, they should shake the dust from their sandals and walk away. Some unfortunately vocal christians tend to forget that wise bit of advice, without which the "go throughout the world and make disciples" command makes no sense.