Pascal’s Wager is an argument in apologetic philosophy which was devised by the 17th Century French philosopher, mathematician and physicist Blaise Pascal (1623-1662). For its time, it was a decent argument. Today, we have much more evidence to believe in the existence of God as a reasonable choice. But for the sake of interest, I’ve listed what his wager was for your consideration:
1) “God is, or He is not.”
2) A Game is being played… where heads or tails will turn up.
3) According to reason, you can defend neither of the propositions.
4) You must wager (it is not optional).
5) Let us weigh the gain and the loss in wagering that God is. Let us estimate these two chances. If you gain, you gain all; if you lose, you lose nothing.
6) Wager, then, without hesitation that He is. (…) There is here an infinity of an infinitely happy life to gain, a chance of gain against a finite number of chances of loss, and what you stake is finite. And so our proposition is of infinite force, when there is the finite to stake in a game where there are equal risks of gain and of loss, and the infinite to gain.
7) But some cannot believe. They should then ‘at least learn your inability to believe…’ and ‘Endeavor then to convince’ themselves.
Pascal summarized the above as follows, “I should be much more afraid of being mistaken and then finding out that Christianity is true than of being mistaken in believing it to be true.” Or to put it the way one Christian did to me when I was an atheist, “If I’m wrong, I don’t wake up. If you’re wrong, you wake up hot!”
If you utilize Pascal’s Wager, you should make it clear what the Gospel is (2 Corinthians 5:21), and let them know that true faith does indeed come from the Holy Spirit. Second, you should urge them to at least give church a try to see what they think.