I've just spent a wonderful hour with a dear Australian brother who has given his lifetime to preaching the gospel and teaching others to do so (no name dropping here!). He made an observation, almost in passing, that really grabbed my attention. "It doesn't matter", he said, "if people don't remember your sermons. Preaching is about making actions instinctive, not giving you more head knowledge." He went on to say that he's a good reader, but doesn't remember being taught to read. He can play the piano but remembers very little about his tuition. He knows how to ride a bike, but can't recall the moment when the stabilisers were taken off.
How true and how liberating! We are tempted, I would suggest, to measure our ministry in terms of how much people can remember of it. And when people say to us "I remember your three points" we get a inward glow. But in fact, the measure of God's word preached is whether people change and if spiritual habits that were unnatural become the norm, become instinctive. We need to pray that our preaching would be effective and not so much that it would be memorable.
It doesn't matter if people don't remember your sermons.