You can get the John Piper and Justin Taylor compilation, The Power of Words and the Wonder of God for free here (and only 7.99 for the Kindle edition). It’s a compilation of various authors (Paul Tripp, John Piper, Mark Driscoll, Sinclair Ferguson, Daniel Taylor, Bob Kauflin) each writing a chapter examining “the life-altering power of our words and their impact in sharing the gospel.”
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