This volume applies form-criticism to the study of prophetic literature. Westermann modifies Gunkel's influential proposition that prophecy combines two different genre (threatening speech and reproach) and convincingly demonstrates that Israel's prophets were broadly similar to ANE messengers.
Classic form-critical study of biblical prophetic speech covering Genesis through Isaiah (including Isaiah's contemporary, Amos). Detailed and scholarly, but generally dry reading. Best served as a reference work, in my humble opinion. The student is left to draw their own conclusions regarding the benefit of Westermann's analysis - not necessarily a bad thing!
A good introduction to the common forms of speeches used in prophetic literature, including adaptations of these forms found as prophetic literature evolved and adapted to meet new historical and social circumstances. Worth your time to check out.