Weren't they meant to indicate your agreement that questioning doctrine was a sin?
I don't believe it says anywhere in the bible that questioning doctrine is a sin
Here is a quote implying quite the opposite:
Now these Jews were more noble than those in Thessalonica; they received the word with all eagerness, examining the Scriptures daily to see if these things were so.
The "more noble than average" Jews studied the scriptures in detail, questioning whether or not the accounts were accurate
Only a great fool believes things without questioning them...
Though, religion does seem to be a gullibility test of sorts