Roger Olson has recently done a couple of interesting posts about whether or not God can change the past. He argues that God cannot change the past. Here are the links:
In the second post he suggests that prayers about the past are probably not effective, and don’t have a Biblical precedent:
And I struggle with why the Bible contains no examples of petitionary prayer about the past at all so far as I know—not even prayers about events not yet known as to their nature and outcome but certain to have happened. This is to me a strong indication that such prayer cannot have any effect other than satisfying some psychological need and causing consternation and confusion.
I agree with Olson that God cannot (or does not) change the past. For example, it does no good to pray that the Holocaust will not have taken place.
Having said that, I do think that prayers about the past can influence what God will have done. I occasionally pray about the recent past. For example, I sometimes pray that a loved one who has been traveling will have made it home safe. I don’t think that God goes back and changes the past because of the prayer, but rather that he will have already done something to have kept them safe because of the prayer. God knows that I will pray later, and can answer that prayer. C.S. Lewis argues for something like this in “Miracles”.
When we are praying about the result, say, of a battle or a medical consultation the thought will often cross our minds that (if only we knew it) the event is already decided one way or the other. I believe this to be no good reason for ceasing our prayers. The event certainly has been decided—in a sense it was decided ‘before all worlds’. But one of the things taken into account in deciding it, and therefore one of the things that really cause it to happen, may be this very prayer that we are now offering. Thus, shocking as it may sound, I conclude that we can at noon become part causes of an event occurring at ten a.m. (Some scientists would find this easier than popular thought does.) The imagination will, no doubt, try to play all sorts of tricks on us at this point. It will ask, ‘Then if I stop praying can God go back and alter what has already happened?’ No. The event has already happened and one of its causes has been the fact that you are asking such questions instead of praying. It will ask, ‘Then if I begin to pray can God go back and alter what has already happened?’ No. The event has already happened and one of its causes is your present prayer. Thus something does really depend on my choice. My free act contributes to the cosmic shape. That contribution is made in eternity or ‘before all worlds’; but my consciousness of contributing reaches me at a particular point in the time-series.
So I agree with Olson that God can’t change the past. But I still think it’s worthwhile to pray about past events, especially events where we don’t know the outcome, and that God hears and can use those prayers.
Side note: Here’s an interesting article about praying for the past by Wesleyan/Nazarene philosopher Kevin Timpe. Prayers for the Past. He calls them PIPs (past-directed impetratory prayers). He argues that PIPs make logical sense for those who hold to Simple Foreknowledge, the Eternal-Now theory (Lewis’ view), or to Molinism. But not for those who hold to Open Theism (because in Open Theism God would at best only have predictive knowledge that someone would pray).
What do you think? Are prayers about the past ever effective?