A sheep says to his sheep friends, "Oh no guys I'm questioning my beliefs!" In the next frame they've all fainted and he says "April Fools!"
The biggest inhibitor for most of us questioning our beliefs is what others are going to think of us.
I've always suggested this: imagine if everyone around you from your parents and siblings and family and friends and everyone was 100% supportive of you being intellectually curious and encouraged questions?
Would you do it? Would you be intellectually curious? Would you entertain questions?
Would you be more inclined to explore what the truth was outside of the prescribed lines?