To summarize, Pascal is saying we must show Christianity is respectable and then desirable before we show it’s true.
I think this is particularly true when it comes to discussing Christianity with the “nothing in particulars” who feel that Christianity is irrelevant. But in order to show that it is desirable, we must be convinced that Christianity is desirable, we must experience it in our lives, and must be able to clearly explain and demonstrate to others that it is desirable.