W. Robert Godfrey writes:
The Westminster Directory of Publick Worship has a significant section on the preaching of the Word. It begins by stressing the spiritual importance of preaching and repeating the words of Scripture that it is “the power of God unto salvation” (Romans 1:16).
Do we today still believe that the preaching of the Gospel is the power of God unto salvation? Do we really believe the Heidelberg Catechism (question 65): “You confess that by faith alone you share in Christ and all his blessings; Where does that faith come from? The Holy Spirit produces it in our hearts by the preaching of the holy gospel…”?
See also Especially the Preaching of the Word by Larry Wilson