I've found the entire collection of R Kent Hughes Series "In the Word" to be helpful for study and excellent series of books for any layman or clergymen. The books are refreshing, up to date on a compelling way to study. I've found Mark especially profitable in my own library of books. Once you've read any of his titles you will find them refreshing & will most likely order his other writings. Well worth the investment.
As a busy pastor I value works that support my sermon preparation and that are not wordy, but terse. Plus the wealth of illustrations and quotes help bring the my sermons to life ! And this series is affordable for the average pastor. Thus a great value to pastors and yet usable and helpful for anyone.