Psalm 53 is almost identical to Psalm 14; both psalms begin the same way:

The fool says in his heart, “There is no God.”

Are you familiar with Pascal’s Wager?

[The text below is from Professor Joseph Incandela’s website.]

It's important always to remember Pascal's project of trying to provide a defense of Christiantiy. Part of the crowd that Pascal hung around with before his conversion did all the things he later identified as diversion: hunting, partying, but especially gambling. Pascal himself is often credited with inventing roulette. So it's not surprising that he uses the device of a wager to try to convince people, who are already gambling, to take a chance on God. That is, if you want to make a point to a gambler, put it in the form of a bet. That'll at least get their attention and disturb their indifference. 

Pascal begins by presenting a decision. Either a person will choose to believe or she will not (there are only two possibilities). As for the way things are, either the God whom Christians worship exists or that God does not (there are only two possibilities). Pascal thought that reason by itself cannot help you decide which path to follow. And in light of this, and the two choices listed above, Pascal asks 'how will you wager?' And note that we have to wager. We can't just not play the game at all. Pascal thinks that by the way each of us is already leading our lives, we are all already making a bet one way or the other. As he says, "There is no choice, you are already committed." He continues, "A coin is being spun which will come down heads or tails. How will you wager? Reason cannot make you choose either, reason cannot prove either wrong."  

If we have to bet, then, how shall we decide? Well, says Pascal, let's look at the possible payoffs (that's just what gamblers do, after all). 

—If God REALLY exists, and we believe (= bet that God exists), we have an infinite gain (heaven).

—If God REALLY exists, and we don't believe that, then we have the potential of an infinite loss (hell, or at least eternal separation from God).

—If God really does NOT EXIST, and we believe that God exists, we essentially lose nothing.

—If God really does NOT EXIST, and we believe that God doesn't exist, we essentially gain nothing.

This can be represented in a table as follows: 

There are really two other versions of this wager in Paragraph 418, but they just build on the point made above that if one has to bet (and we do), then it's always more rational to wager on an infinite gain. An infinite gain will always outweigh even a finite loss or gain. Therefore, it's always more rational to bet that God exists. As Pascal says, if you wager and win, "you will win everything." 

Pretty interesting stuff, huh? —Andrew