Treatise on Good Works: Luther Study Edition Paperback – Illustrated, February 1, 2012

Luther gets to the subject and discusses it from a Reformation Era standpoint. With extrapolation to our time, it is still relevant. It is still the quandary of works vs grace based thinking/faith and hasn't changed.

Probably one of the best book I have ready about Christian ethics. Luther viewed the law from the side of faith rather than as civic law