I've heard a lot of translated sermons both in the States and Eastern Europe. It's probably one of the toughest, tedious, and most frustrating things a pastor has to do. I've never preached through translation so maybe I lack credibility to talk about this.
That said, I've sat through several good ones and several poor ones. The best and the worst of which I've experienced in the past month here. So, I've decided to compose some guidelines in the hope that someone going overseas will read them and deliver a high-quality sermon.
Why it matters: If it's not quality, it doesn't reflect badly on the preacher but rather on his national translator. He/she has to live with shame, while the preacher gets to leave the country, often oblivious to the fact that he embarrassed the translator!
I asked my father-in-law (very experienced at this)for his insights and he gave me a list of 14 points, some of which I'll include with my points.
1. Write out your entire sermon beforehand. I don't care if you don't normally do this, you need to if it's going to be translated. Word-for-word.
2. Have someone edit your sermon to take out any wordiness and American idioms. Just like you'd have someone edit a paper you turned in for Seminary or grad school. Ex: Don't say "go out of," say "leave." Don't say "under the table," say "illegal," etc. Try also to eliminate "churchy" words.
3. Print out your edited copy and give it to your translator at least a day before you preach. Let him/her become familiar with it, look up words, and ask questions about it. There may be some necessary "churchy" words that he/she needs help understanding.
4. Have a Bible in the local language ready for all quoted passages. Don't expect your translator to translate a verse from English exactly as it's written in the congregants' Bibles. (You would think this is a no-brainer, but all too often...)
5. Keep your printed copy in front of you as you preach. Read from it with passion. Try not to look down or read or as you speak; you have plenty of time to prepare your next sentence or 2 while your translator is talking, and can look up at the congregation as you speak as if you're not reading.
6. Don't ad-lib. The last thing a translator wants to hear is "oh, by the way..." Nothing ruins a well-translated sermon more than a poorly-translated tangent.
7. Don't include jokes without going over them beforehand with your translator. He/she can likely think of a similar joke, or can modify it to make it more understandable to the locals. Literally-translated jokes almost never make sense.
8. Don't quote from old hymns, anecdotes, or anything King James and expect the translator to make it understandable. Russian Baptists have many of the same (or similar) hymns that we do. If you want to quote from it, ask someone to show your translator the equivalent hymn in the Russian hymnal and let them read it.
Last week, I saw an American pastor try to make the connection "I know you know the lyrics to an old hymn.... 'sin had left its crimson stain...'" His translator didn't know what "crimson" was, and may not have understood "stain. " The American pastor eventually had to say this passage 3 times and eventually broke it down to "ugly red spot." It took literally 5 minutes and his point was completely lost in translation and in the frustration of having it translated.
*Warning!* If your translator has to ask you to clarify something during the sermon, then you've likely already lost the congregation. Get out while you can!
9. Be humble. Give a greeting from your home church, and be sure to tell the congregation how much you appreciate their hospitality.
10. Avoid telling stories from your own church unless you make your point absolutely clear. 99% of the congregants have never been to America, have no idea what American culture is really like, and cannot relate to your average congregant's life in the slightest. You go out on a limb when you say: "A man in my church is a stock broker, and understands that life is often uncertain," for example. There's a million better ways to generalize that in a way they understand (work and income are quite uncertain outside of America, too. What does having a stock broker have to do with that, and does that really matter to your sermon?).
11. Talk about what Christ is doing in your life, personally. That will help them relate to you as a fellow brother and not just a foreigner.
The first 7 points are ABSOLUTELY necessary! It doesn't matter if you never do these things for preaching at your own church. You're NOT at your own church, some things are NOT universal, and you need to be FLEXIBLE when working in another culture. Do all of the above, and you can ensure having your sermon effectively delivered. They ought to teach this stuff in seminary.