Appeal to faith

An appeal to faith (or an appeal to belief) occurs when someone argues that you must first accept the truth of a statement in order to be able to rationally accept it.

The fallacy is a form of circular logic and an informal fallacy.

Form
In reaffirming believers:

In shutting down nonbelievers:

Explanation
Faith, by definition, is belief that does not rest on logic or evidence. Faith depends on irrational thought.

Saying that a belief is immune to criticism from nonbelievers is special pleading and never fails, making it circular logic.

Examples

 * "Once you believe it, you will understand!"
 * "If you accept the Lord, you will understand!"
 * "If you would only take Maslow at his word, you would finally get it!"
 * "The way in which I know Christianity is true is first and foremost on the basis of the witness of the Holy Spirit in my heart. And this gives me a self-authenticating means of knowing Christianity is true wholly apart from the evidence." — William Lane Craig combining an appeal to faith with several other fallacies, including an appeal to authority (and a faith-based one at that).