Don't Waste Your Life by John Piper

Most people slip by in life without a passion for God, spending their lives on trivial diversions, living for comfort and pleasure, and perhaps trying to avoid sin. This book will warn you not to get caught up in a life that counts for nothing. It will challenge you to live and die boasting in the cross of Christ and making the glory of God your singular passion. If you believe that to live is Christ and to die is gain, read this book, learn to live for Christ, and don't waste your life!

I'd recommend this book for personal reading and for discipleship. In a very easy-to-read style, John's writing will provoke you to steer your life on to the path of true joy.