Interesting event regarding prayer

I was walking down a street and a young girl (18 or so) basically started a conversation with me. She was 'crazy.' All over the place. It was the usual situation where you are half thinking how do I get out of this without being taken for a ride (she was asking me to drive her to somewhere, I couldn't get a clear answer where) and how do I help her. It turned out she lived nearby. She was across the street from a hospital, and had just been in the emergency room but had left without getting help. So my main game plan was to convince her that that was the best place for her for now. People in there could help her.

Here's the main point: I wanted to say something regarding evangelization. So I kind of lamely threw in in a part of the conversion "Read the Bible." It was awkward and out of context of the conversation. But I wanted to just say 'read Bible' in some way. But then as she decided to cross the street and go back into the emergency room I said: "I'll pray for you."

I could *feel* a calm reaction it produced in her at those words. She didn't respond with words, but I could feel a response. It surprised me. Before she was all hyper mentally, changing topics, paranoid.

Now, today I was looking through a book on spiritual practices written by Donald Whitney (Spiritual Disciplines for the Christian Life). I'd opened it to a random page where he was saying (paraphrase) "I've noticed that when I tell somebody I will pray for them it always has a profound effect on them. People like hearing it. It shocks them." That's a paraphrase because I don't have the book at hand.