The wager is simple. There are 4 possibilities.
- You become a Christian and Christianity is true
- You become a Christian and Christianity is false
- You don't become a Christian and Christianity is true
- You don't become a Christian and Christianity is false
With #1 you win infinitely. With #2 you lose something but only finitely. With #3 you lose infinitely. With #4 you win something but still not much because life is still terrible. On balance, if the chance of Christianity being true is non-trivial you are right to bet your life on something that pays. Atheism has no upside for being right. You just know life is awful before everyone else does but there is nothing that can be done about it.
Kreeft draws the distinction between those seeking truth and those seeking joy. Pascal addresses both groups. The wager is only for those who are primarily seeking joy. What makes the most sense from a personal pain/pleasure standpoint? He does not ignore those who want to believe what is true regardless of the consequences. He has already argued that Catholicism is at least as likely to be true as anything else. You just have to read the whole thing.
What Pascal's wager does is lower the bar of certainty. We can come to the conclusion that Catholicism might be true but not be sure about it. Then we look at how much trouble and discomfort would be involved to reorder our lives. We might wonder whether or not it is worth it. Pascal's wager can be useful there.
Think of the person in scripture who says, "Lord, I believe. Help my unbelief!" That kind of person that has been toying with conversion and never seems to take the plunge. You don't have to wait until you have a faith that can move mountains before you come to the sacraments. Just come as you are and let God deal with you remaining doubts over time. Your conversion is not the end of your religious journey but really the beginning.
When we say we are saved by faith the question always comes, "How much faith do you need?" Protestants have no real answer. Catholics can't say when you don't have enough but they can tell when you do. If you have enough faith to come for baptism or come for confession then you have enough faith to be saved. You may still have many doubts but God honours the faith that brought you. When the priest performs the sacrament you are brought into a state of grace even with that imperfect faith.