Faith is to believe what you do not see; the reward of this faith is to see what you believe - Augustine of Hippo
Pascal treats believing in God as a bet or "wager". If you believe in God, you have to give up some pleasures on earth but if you turn out to be right you get eternal joy; if you're wrong, there's no afterlife and you don't experience anything.
If you disbelieve in God, you can enjoy yourself a bit more here on Earth but, if you're wrong, you get eternal suffering.
When you weigh up what you stand to gain and what you stand to lose, it makes more sense to believe in God.
God of Abraham, God of Isaac, God of Jacob
Not of philosophers nor of the scholars
- Blaise Pascal