The question is a little bit difficult to follow, but the reference really helps in understanding where this is coming from.
Fideism is a term usually applied to speak negatively of a view though a few have owned up to the term. (Note how the article describes it as an "ascription").
To call someone a fideist is to maintain that they believe faith is opposed to reason rather than somehow compatible with it.
The Pascal quote (which I don't have the broader context within Pascal off the top of my head) is referring to 1 Corinthians "foolishness to the Greeks" description of the Gospel. The idea is that some claim is inscrutable to reason.
We might reword it as :
- X is true such that no argument can be given for X.
- Ergo, to ask for an argument for X is to misunderstand the nature of X.
- X is true BECAUSE X is foolishness (i.e., cannot be known through argument). = if foolish, then true
- There is an argument that concludes X is true
- Then X is false (per modus tollens 1,2 )
presumably you're going to need some qualifiers to make such an argument work (it would be a terrible position to hold that anything that is foolish is true).
We can find somewhat similar arguments in Kant about the nature of things-in-themselves and understanding them (namely, that understanding does not apply to things in themselves but rather things as objects).