People hold their belief system to be so sacrosanct that they feel it to be blasphemous to raise questions at it. How can such people be told the importance of verification of their beliefs? In every age there are people who believe that thinking against the system or tradition is a sin. Such people have been there in the past and will continue to exist. Try to explain to them. Even angels questioned God. God Himself set the example of being questioned by the angels and of responding to them. When God created Adam, the angels said: You are creating humans who would spread evil on earth, indulge in killing and so on. God did not express disapproval and ask them to be quiet. God answered and explained the matter to them. God explained to the angels, and gave a demonstration of how to respond to questions. When God Himself invites questions, how can a human being have the right to say it is wrong to question. This is completely baseless. You have to explain to them that their thinking is not right.