This might seem like a strange post coming after yesterday, but as I said I don't see any issue with bringing up the issues with a particular teaching or idea.
Yesterday I walked in on a conversation my grandfather and his brother were having. I'm not sure how it started, but within the first few words I knew where my grandfather was going, and why it was wrong. He was bringing up Pascal's Wager.
Pascal's Wager basically says that either God exists, or God does not exist. So it is better to live life as if God exists, since if it turns out there is no God you lose nothing - where an atheist, if they were wrong and there is a God, would lose everything.
Now, anyone who understands that there's more than one religion can see the most obvious flaw here - Pascal's Wager puts forth only two options, but there there are numerous Gods and religions one could choose from. How do you know you'll get the right one? It also assumes that if a God exists, they will punish atheists for not having faith, which is not a teaching of all religions.
If we narrow it down to the options where non-believers will be punished (since if there is a God who doesn't care, taking such a view would mean you still "lose nothing"), we're still left with several options. There's no guarantee that you will choose the right one. A Christian who lived their life believing in God should be "safe" according to Pascal - but if that Christian dies, and it turns out maybe Islam was true? Well, things aren't looking so good for them, after all. (I find that when using that particular example, even in reverse, many are more likely to want to jump on the bash Islam wagon, rather than sticking to the issue. Don't be derailed!)
Now this particular criticism was addressed by Pascal, well, somewhat. Pascal basically calls this argument a "trap" that he won't fall into. That anyone actually interested in knowing the truth would study, and come to his same conclusion that all "pagan" religions (that is, all religions aside from Judaism, Christianity, and Islam) come down to superstition and ignorance, and aren't actually worth looking at in any detail. He basically comes to the same conclusion about Islam. Yet, the only reason anyone "rejects" Christianity is because they haven't looked at it in detail. Pretty easy to see why this is a flawed, and indeed hypocritical argument.
This is not the only flaw with the wager, though. It also assumes that an all knowing God isn't going to care that you were essentially going through the motions just to be rewarded, as it's quite hard to force true faith. Of course, many Christians don't actually seem to understand why this is an issue. (Matthew 7:21, anyone? Some scholars see this verse as applying to false faith, among other actions.) Others say faking faith leads to real faith, and that if it doesn't you just "weren't trying hard enough." It's quite hard to explain to such people why that is a flawed view. Of course, this eventually gets more into the issues with a God who would create an eternal hell, worshiping to avoid Hell, and so on. Perhaps that would be better left to another post, for another day, though.