With beliefs, one begins with a presupposition, and works towards rationalizing it. In free thinking, one follows the evidence and logic to arrive at a conclusion, regardless of the expected outcome.

My response to OP...

Mike Tyson vs. Pee Wee Herman.

For a rational thinker, belief is tentative knowledge that is subject to revision as more facts are learned.

Belief in a religious context is specifically the act of holding contradictory ideas in one's mind simultaneously without being aware of the contradiction. Educated believers are aware of the real world and how it works, but they also hold the idea that it is magically controlled and manipulated by an invisible sky-spook. They know that consciousness depends on a functioning brain supported by a living body, but they also believe that they will somehow survive death.

George Orwell coined the name "doublethink" for this phenomenon in "1984".

This reminds me of the Mike Myers "Coffee Talk" skit on SNL:

"Rational free thinking versus belief. Talk among yourselves!"

Everyone has beliefs.

The 'rational free thinker' and the irrational theist have beliefs.

A belief is simply, the psychological state in which one is convinced a claim, premise or proposition is true, or likely true.

In other words, if one is convinced a claim, premise or proposition is true, they have a belief.

The reasons one is convinced, is where the rational thinking part comes in.

Rational reasons for having a belief: demonstrable and falsifiable evidence, reasoned argument, and valid and sound logic.
Irrational reasons for having a belief: 'feelings'. ancient texts, fallacious arguments, raised with a specific belief, etc.

For some reason, it seems that the word "belief" became a dirty word among some atheists. As if, a belief is always irrational, or without evidential warrant. When in truth, there are good reasons to hold a belief, and bad reasons.

Obviously a theist troll out for his first drive by post.