This parenting book stands above the rest.
There are two things that Farley does particularly well that I'd like to draw attention to.
First, he distances himself from those that insist we must remove our children from the world (e.g. public schooling, Halloween, etc) in order to protect them from the world. He acknowledges that parenting always involves some protection, but he righly points out that an isolationist mentality often ends up with legalism. Farley recommends parents raise up their children not by changing and controlling their environment (things external to their children), but by going after their hearts.
Second, he picks up a theme from a great parenting book from the 1970s, How to Really Love Your Children, and emphasizes the importance of affection and different ways to show it to your children.
In places Farley sounds a lot like Tripp's Shephering a Child's Heart, but I think Farley is clearer in his main point of going after heart issues. Gospel-Powered Parenting may be the best parenting book I've read.