Why the Holy Spirit should be restricted so that He can only be at work at the moment a sermon is delivered and not in the thoughtful and prayerful preparation beforehand, I don’t know. The same mistake was made by an actual preacher who used to prepare the first half of his sermons and then freewheel the second half, wishing to “depend on the Holy Spirit for inspiration.” One astute lady listening to him one day was perplexed by the change that took place halfway through the sermon. Afterwards she asked the preacher what happened. So he explained his method to which she replied, “That is strange. You are a better preacher than the Holy Spirit!”