I'm undertaking the task of learning Theological German. I've heard that April Wilson's work, German Quickly is the best book in this regard. The key to this book is that it is a grammar for reading German. Unfortunately, I'm not delving into the task of learning to speak or hear German. That's not very important to me.
I'm learning Theological German because there is a wealth of material available today in the theological arena that's only in German. Though many of the theological works in German have been translated into English (thankfully!), much has not. Many articles and books are in German and so, for my doctoral program, I'm learning German to supplement my studies at BBS.
Pray for me as I attend class and work through this book over the next month and a half. So far, I've got the alphabet down. I'd say I've got a ways to go! :=)