Interesting choice you offered for Christian. I find it telling you would separate it as such, I think you are selling your own awareness, of believing, or not, short.
For faith to be real, it has to be absolute, not kinda pregnant.
Man inherently is not capable of its requirements, as he is fallen.
Yet, salvation is still possible.
Faith is not having to jump through hoops, or having a government sanction it with a pledge, or scripting verse on its currency, yet, that is what many "want"........
Believing is an extremely personal relationship, and needs no further exterior, or ulterior support, for it to sustain.
Maybe I am reading too much into your reason to separate the question, but from my POV, it shows to me you understand something about "believing" others, that profess to, don't.
On a personal note, my relationship with God was superfluous, for what I was lacking, until I came to him honestly. How that translate in my own life was this.....
I believed I had to pretend I was happy. I would praise him when I didn't feel it, or mean it.
Not until I accepted my anger at him, and the unjust things that I saw and experienced in my life, and gave him both barrels of buckshot I had been harboring for ALL my life, did it change.
I feel this was really all he was waiting for, me being honest in ALL things.
I can not grasp repair, if I don't acknowledge what is broke.
I kid you not, I had one of those awakenings that was instantaneous....
What use to baffle me, did no more.
I had knowledge of things that I had no clue, I even knew about such things
In short, his spirit filled me as promised, for I am way too stupid to acquire this understanding on my own
And this "knowledge" is why I think your reasoning to separate the question thus, suggest to me you have a deeper understanding of faith, than a lot of confessor portend.
You may breath now