Once in seven years I burn all my sermons; for it is a shame if I cannot write better sermons now than I did seven years ago.
I said that Wesley's opinion was actually quite the opposite. He said he would be glad to know where I got that information from. Well, it's been thirty years and more since I read Wesley's Journal and came across that entry, but I went looking, and my memory had not failed me. Here is the actual quote from The Journal of John Wesley for Tuesday, September 1, 1778.
I went to Tiverton. I was musing here on what I heard a good man say long since -- "Once in seven years I burn all my sermons; for it is a shame if I cannot write better sermons now than I could seven years ago." Whatever others can do, I really cannot. I cannot write a better sermon on the Good Steward than I did seven years ago; I cannot write a better on the Great Assize than I did twenty years ago; I cannot write a better on the Use of Money, than I did nearly thirty years ago; nay, I know not that I can write a better on the Circumcision of the Heart than I did five-and-forty years ago. Perhaps, indeed, I may have read five or six hundred books more than I had then, and may know a little more history, or natural philosophy, than I did; but I am not sensible that this has made any essential addition to my knowledge in divinity. Forty years ago I knew and preached every Christian doctrine which I preach now.
As you can see, the quote is accurate, but it is an internal quote. Wesley is quoting somebody else, somebody with whom he does not agree. But all the quotation sites I skimmed on the internet have the quote as from Wesley, by Wesley, expressing Wesley's views.
BTW, I agree with Wesley. I do a lot of re-preaching of old sermons. After all, my current parishioners haven't heard them before. And why should I deprive them of my "Greatest Hits?" (Besides, it gives me time to do other things besides write new sermons all the time.)