I first saw this prayer when I was in college (somewhere between 1985 and 1989) in a book called Balcony People by Joyce Landorf Heatherley. The book was clearly a traditional Christian "gift" book, so imagine my surprise to find a prayer like this on the preface page.
It calls out those who talk about their faith without doing anything concrete to live it out. I remember reading it in a Sunday worship service with a clear note of disdain in my voice even then. I felt surrounded by people who did exactly that, even though I wouldn't be able to articulate that feeling for a long time. I'd go through similar struggles and think, "Don't just pray about it--do something!"
I can't always do anything about injustice these days when money is tight and my mobility is limited. This is a reminder to myself (and perhaps some of you?) to find a way. Don't just pray about it--do something!