This book by Sinclair Ferguson is being offered free in audio format by the people at christianaudio.com
The book has been a great blessing to myself and many others on the PB.
Enjoy!
This is easily one of the most helpful books published in the last few years. I think it's telling that once it appeared, the yelling back and forth about antinomianism/legalism among Presbyterians got noticeably quieter. In the book, Ferguson is a clear teacher without being accusatory, and sets down a foundation that's hard for anyone to disagree with.