Really good stuff here from J.D. Greear. Below are some excerpts but I would encourage you to read the whole thing:
Because getting into spiritual conversations can be so nerve-wracking, it’s good to have a few tools in your tool-belt that can get things going. Now, a tool is only as good as the person wielding it. No evangelistic tool I’ve seen is a magic bullet, and there is absolutely no substitute for Spirit-fueled love for our lost neighbors. Fortunately, we do not need to choose between genuine compassion and helpful evangelistic aids.
One of the more unwieldy evangelistic tools out there is the “diagnostic question.