Hans
First, I hope you don't mind me shortening your moniker.
Re: prayers...the point of them isn't to put something into action. Prayers offer (those who have faith) comfort.
That's all they really do.
Think of it like saying, "Good luck" to someone, or keeping your fingers crossed when the lottery numbers come up. These actions don't have a bearing on what is going to happen, but it makes people feel better. It gives people a sense that they can somehow influence what's coming.
However, if prayers were all Theresa May was to do, then I would agree with you that they were a waste of time...but they're not.
Oh, and by the way - this story was leaked. I understand posters here saying that it's a private matter, but the Prime Minister's office absolutely wanted us to all know about it.