It's quite possible that nothing helps you more than something you probably do your darndest to live without.
The feeling of doubt.
Without doubt, there is no questioning. Without questioning, there is no considering. Without considering, there is no real thinking.
Without real thinking, there is no mental or emotional growth.
But that doesn't mean you have to question everything. Some things have withstood the test of time.
Like the phrase "withstood the test of time." It's a cliché, a phrase that's become trite from overuse.