In On Christian Doctrine 4.62 Augustine argues that it’s perfectly appropriate for a pastor to use sermon’s prepared by someone else. According to him, we should just face the fact that some people are gifted speakers, but not very skilled at study. To use Augustine’s distinction, they are fine “preachers” but they are not very able “teachers.” And, as long as the speaker does not use another person’s work dishonestly (i.e. claiming it for his own), and as long as the church has a coherent teaching (preferably through a singular teacher), there’s nothing wrong with this.
There are, indeed, some men who have a good delivery, but cannot compose anything to deliver. Now, if such men take what has been written with wisdom and eloquence by others, and commit it to memory, and deliver it to the people, they cannot be blamed, supposing them to do it without deception. For in this way many become preachers of the truth (which is certainly desirable), and yet not many teachers; for all deliver the discourse which one real teacher has composed, and there are no divisions among them.
Augustine goes on to argue that the real “thief,” the true “plagiarist,” is the one who preaches what is not true in his own life: “it is the man who speaks well, but lives badly, who really takes the words that belong to another.”
What do you think? Would you have any problem with a preacher who didn’t prepare his/her own sermons as long as they were honest about it?