What the Bible says about social justice. Preaching the gospel of salvation and working to alleviate suffering in this world are NOT two opposite ends of the spectrum; they are intertwined in Scripture and should be in our lives and ministries as well.
My friend Jen recommended this book, Wordsmithy, to a new blogging group I belong to (that she originated) on facebook. It is by Doug Wilson, and from what she says you can expect it to improve your writing. I'm planning to look further into it! :O)