How Long Should a Sermon Be?

The question came to me as I started reading a book by Peggy Noonan. On Speaking Well is an old book (1998), but it was published before Noonan became one of my favorites, so I hadn't encountered it before. It was on a $5 table at a booth in the CCCC exhibit space, so I picked it up.
Here's her very first piece of advice: "No speech should last more than twenty minutes." As soon as I saw this, I thought of all the sermons I've heard--and delivered--that have been way longer than that, many of them twice as long.

I figure Noonan hasn't attended many, if any, churches like those where I've worshipped or spoken. And I'm pretty sure she's never delivered a sermon. But she's given lots of speeches, and written many hundreds more of them. Here, from President Ronald Reagan's most famous speechwriter, is her advice:

No speech should last more than twenty minutes. Why? Because Ronald Reagan said so. Reagan used to say that no one wants to sit in an audience in respectful silence for longer than that, if that. He also knew twenty minutes is more than enough time to say the biggest, most important thing in the world. The Gettysburg Address went three minutes or so, the Sermon on the Mount hardly more. It is usually and paradoxically true that the more important the message, the less time required to say it.
I would add that forty years of the habit of television has probably affected how people receive information. They are used to fifteen- or eighteen-minute pieces on 60 Minutes. . . .  They are used to twelve-minute segments within the arc of [a TV] drama. . . . They are used to commercials interrupting the flow of thought. They are not used to watching forty- and fifty- and sixty-minute presentations without a break, and there is no reason to believe they want to get used to it.
So keep in mind what Hubert Humphrey's wife is said to have advised him: "Darling, for a speech to be immortal it need not be interminable."

Again this week I listened as a young preacher spoke about his church's adjustment to a music style that will appeal to today's generation. But I can't remember when I've heard a preacher talk about adjusting his preaching style to appeal to today's generation. I know many preachers do more than speak glued to a podium. I know they move around the platform and try to speak conversationally. I know they use PowerPoint. I know many preachers think about how to engage today's audience.

So here's one more principle to consider. For every thoughtful preacher, and for myself, I'm adding this advice from someone in tune with today's listener: No speech should last more than twenty minutes.