Footnote #2 in Walther’s Lutheran Pastoral Theology on page 96.

Augustine writes: “Anyone who wanted to say that people need not care what and how they may teach because the Holy Spirit Himself makes teachers, he could also say that we also need not pray because Christ says, “Your heavenly Father knows what you need before you ask Him for it.” (On Christian Doctrine 4.16 [cf. NPNF 2:585]).

Sacrecrius writes: “It is great insolence, wickedness, and presumption; yes, a grave sin deserving God’s great wrath and punishment; yes, contempt for God and His Word and sign that there must not be any fear of God if one has the time to prepare for sermons and he does not prepare for the sermons bu runs to the puppet like a pg to its trough. And it is pointless to object on the basis of one’s skill and ability or even practice and experience. For no matter how learned you are and no matter how long you have been preaching, you must still prepare (Pastoral, p 43).

Quenstedt writes: “Especially at the beginning, it is most advisable to write out the entire sermon word for word. For the younger and less experienced, this is not only useful but also necessary for gaining self-confidence as well as for acquiring a repertoire of words and for the sake of memory. Over tie, however, I believe a change can be made. Especially when there is no alternative because of the burden of other affairs, those with more experience and a greater repertoire of knowledge and words may carefully write out the main points, the arguments of the individual parts, the testimonies [of Scripture], and examples, and likewise add the words appropriate to the topic as necessary” (Ethic. Pastoral., pp. 113ff). CFWW