Bhagavad Gita, Chapter 3, Verse 32

But those who, finding fault with this teaching, do not follow it, deluded in all knowledge and without discernment, know them to be ruined.

Rejecting something before really understanding it doesn't protect anyone, it just closes a door that could have helped.

This isn't about punishing doubt, it's naming a real consequence. Dismissing guidance out of pride or confusion, rather than sitting with it, is described as its own kind of self-inflicted harm.