Lately I've been seeing a lot of discussions from skeptics who mock and deride believers for praying.
Some comments from atheists look like this:
The atheistic meme is this: your prayers are useless because your God's going to do what God wants to do anyway...and even you Christians admit this with a resigned shrug when you don't get what you pray for..."I guess it wasn't part of God's will". So what's the point of praying?
And the Christian response is often, "We pray because it changes us. It doesn't necessarily change God, who is all sovereign, all powerful".
That's a good response. But I think there's also a very, very big apologetics rejoinder is often forgotten:
Prayer can indeed cause God to change his plan.
Now, this of course needs to be understood with some nuance.
In one sense God is indeed sovereign, and his will immutable.
But in another sense, God does allow us to change events by our prayers. God gives us the "dignity of causality" (one of my favorite phrases!)--that is, we have been given the great privilege of actually being able to cause events to change because of our actions.
In fact, we see this evident every day, if not necessarily in our spiritual lives, but in our natural lives. We see that when we plant seeds for corn, we get corn on our plates. We don't just assume, as Ricky Gervais implies, "Hey, God knows I'm going to need corn on my plate, so let me just sit back at the dinner table, and God will provide it!" We plant seeds, and then we get corn. God is indeed sovereign, and if he wanted, he could send corn down from the sky, but we have been given the privilege of actually causing corn to grow in our fields, so we take actions to effectuate this process. If we don't plant the seed, we most likely aren't going to get the corn.
Similarly, we see that when we plant seeds for a cure for our loved one, through a novena, for example, we get a cure "on our plate". We don't just assume, "Hey, God knows that we want a cure for Aunt Martha, so let's just sit back and wait for her to come home from the hospital!"We "plant the seeds" for her cure by our Prayers of Petition. Without the prayer, we may not get the cure.
If you say that we should not pray because God already knows our needs, then as CS Lewis says, "...it would be equally foolish and impudent to put on a mackintosh - does not God know best whether you ought to be wet or dry? The two methods by which we are allowed to produce events may be called work and prayer. Both are alike in this respect – that in both we try to produce a state of affairs which God has not (or at any rate not yet) seen fit to provide 'on HIS own'. And from this point of view the old maxim laborare est orare (work is prayer) takes on a new meaning. What we do when we weed a field is not quite different from what we do when we pray for a good harvest."
Finally, a quick comment regarding the inane "You pray for me, I'll think for you" meme--this taunt creates a peculiar (and ubiquitous) Either/Or false dichotomy. For some weird reason atheists have decided that one cannot both be a prayer AND a thinker. The Catholic response is, "We are perfectly capable of the Both/And. We can pray and think at the same time!"