Not only have they stayed on Christian bestseller charts, they have climbed to the top of the lists kept by?among others?The New York Times, USA Today, The Wall Street Journal, and Amazon.com. The No. 2 ranking on the Times's list is all the more significant because the Times doesn't monitor sales in Christian bookstores.

For LaHaye and Jenkins, the seven-plus years of writing about the end times have been anything but a tribulation. A lot of work, certainly, but labor rewarded with stories of lives changed.

"We have received tens of thousands of letters from people who say they've been challenged to live more aggressively evangelistic lives," Jenkins says. "We've heard two thousand stories from people who have received Christ. We heard about an old man who read the books through a magnifying glass and was saved. He said it was not from what he read through the glass but what he read through his heart.

"Some have said the books are the longest, most expensive gospel tracts they've ever seen."

Though successful at the bookstores, the series has drawn its share of criticism. In World magazine, Fred Baue called Apollyon "TV for readers" and wrote that "the characters are so comic-book-like and the novel itself so poorly written ? that serious theological concerns are trivialized."

But the series has received critical praise as well. Matthew Scully, a contributing editor for National Review, wrote a glowing essay that reviewed the first four books of the series. "It's a highly imaginative piece of work," he wrote in December 1998, "with much Christian wisdom and a message of readiness relevant enough to all regardless of which comes first?one's own last days or the world's."

Roy Fish, Distinguished Professor of Evangelism at Southwestern Baptist Seminary in Fort Worth, Texas, is an unabashed fan of the books, although he doesn't buy the authors' scenarios. "I've read them all," he says. "I have a little bit of a problem with the eschatology [the study of last things] that's set forth. I'm not sure everything they say is going to happen will happen. It's extra-biblical, not anti-biblical. But I know there are multitudes of people who go along with this." Fish notes that plenty of well-educated Bible scholars have contended for this pre-tribulation interpretation of Revelation.

"I don't have a scheme of my own," he says. "I contend for the return of Jesus. I contend for a millennium and that Jesus will reign on earth. He's coming, he's going to set up a kingdom. That's about as dogmatic as I can get. The minute details ? no man knows the details. I don't think God intended for us to be able to work it out on charts."

His concern about speculation aside, he says the books are a welcome evangelistic tool. "It's like Hal Lindsey. Probably thousands of people were saved through reading his book," Fish says. "I'm for anything that prompts people to look to God and to read the Bible. ? The books make me more aware of the coming of the Lord and encourage me to live in that anticipation.

"I think there will be many people saved. The books really make people aware of the dangers of being outside of grace when the Lord appears."

That is exactly what the authors say they want. They never mention the year 2000 or looming fears of the Y2K computer bug. In an interview last year, LaHaye told Focus on the Family's Citizen magazine that he and Jenkins weren't predicting a time frame. His vision was to write a novel that "would wake people up to the fact that Jesus is coming again, and they need to be prepared."