The preaching that kills may have insight and grasp of principles, may be scholarly and critical in taste, may have every minutia of the derivation and grammar of the letter, may be able to trim the letter into its perfect pattern, and illume it as Plato and Cicero may be illumined, may study it as a lawyer studies his text-books to form his brief or to defend his case, and yet be like a frost, a killing frost. Letter-preaching may be eloquent, enameled with poetry and rhetoric, sprinkled with prayer spiced with sensation, illumined by genius and yet these be but the massive or chaste, costly mountings, the rare and beautiful flowers which coffin the corpse. The preaching which kills may be without scholarship, unmarked by any freshness of thought or feeling, clothed in tasteless generalities or vapid specialties, with style irregular, slovenly, savoring neither of closet nor of study, graced neither by thought, expression, or prayer. Under such preaching how wide and utter the desolation! how profound the spiritual death!
Edward M. Bounds, Power through Prayer (Oak Harbor, WA: Logos Research Systems, Inc., 1999).
I have just completed a new Small Group Bible Study on Prayer. It is part of the Good Questions Have Groups Talking subscription service. See https://www.mybiblestudylessons.com/