But two years after that speech, the church's global missionary force has dropped from near 62,000 to about 51,000, a fact that may have contributed to the declining number of new LDS converts from around 300,000 to 241,000 in 2004.
It wasn't a surprise, said LDS spokesman Dale Bills in a recent interview. "In raising qualification standards for missionary service, the church anticipated some decline in the number of missionaries serving."
Still, it has left Mormons all across the country and on LDS weblogs debating the benefits and costs of the change.
Some see the value of culling slackers - the unconverted and the lazy who are a drag on the system. Others mourn the loss of some who would have been given a second chance under the old rules.
"The day of the 'repent and go' missionary is over," Ballard said in the "raising the bar" speech. "Some young men have the mistaken idea that they can be involved in sinful behavior and then repent when they're 18 1/2 so they can go on their mission at 19. While it is true that you can repent of sins, you may or you may not qualify to serve."
Instead of using every available young man willing to commit to the rigors of a two-year mission for The Church of Jesus Christ of Latter-day Saints, Mormon leaders wanted only "worthy, qualified, spiritually energized missionaries," Ballard said. "This isn't a time for spiritual weaklings. We cannot send you on a mission to be reactivated, reformed, or to receive a testimony. We just don't have time for that."
Rumors abound about what might prevent someone from getting a missionary assignment. Some claim that taking medication for depression or for attention deficit disorder (ADD) would make you ineligible. Or having seen a psychiatrist. Or being overweight.
"That is a myth," says Quinton Harris, former director of LDS Missionary Medical Committee. "There are very few things that would inhibit a person from going. Each application is dealt with on a case-by-case basis."
A person who suffers from schizophrenia would probably not be able to serve, he says, and bipolar disorder is also difficult to manage. But if a person takes medication, he could still go.
"We would like anyone with emotional problems to be evaluated, then get stabilized on medication before he goes, then stay on it in the field," Harris says. "If they're stable on medication, chances are they are going to succeed."
In the past, potential missionaries were not thoroughly screened for emotional problems. Many didn't want to admit they had seen a therapist or taken medication. Or they thought that they no longer needed to take it and they would be fine. On their missions, some of them became emotionally ill and had to go home early for treatment.
"Any condition you have before you go gets worse when you get out in the field," Harris says.
From his perspective, raising the bar has been enormously successful - if only to make bishops and stake presidents aware of their missionaries' emotional needs.
Under this new system, each potential missionary is evaluated by ecclesiastical authorities for mental, physical or social problems. Some conditions, such as sexual, alcohol or drug addiction, would preclude a young person from going on a mission. But applicants who have demonstrated their ability to control some of these behaviors can be considered for service. Young women who have had an abortion are generally ineligible.
Unfortunately, some candidates who have taken medication for mental illness feel they have been unreasonably excluded. So do some who were once sexually active but then became celibate.
"I like the image of a missionary who had his own struggles and is out there trying to help potential converts with theirs," says John Hatch, a history major at the University of Utah, who served a mission to upstate New York in 1995-97. "It becomes about both of them - not just the convert."
Hatch also worries that raising the bar makes the LDS Church "more elitist."
"It makes it easier for those already struggling to fall along the wayside, while those predisposed to obedience will gain even more kudos for making it as missionaries," Hatch says. "There's no way I'd be in the church today if I hadn't gone on a mission."
Some bloggers have argued, however, that the decline in missionary numbers has nothing to do with higher standards. They attribute it to a sort of reverse baby boom with fewer 19-year-old boys, especially in the United States.
Bills believes the "reduction in the worldwide population of missionary-age young adults" has been a factor, but not the sole reason for the declining numbers.
Whatever the cause, the church wants to reverse the trend.
During LDS General Conference in April, Ballard took up the subject of missionary work again.
He quoted Church President Gordon B. Hinckley as saying, "The message to raise the bar on missionary qualifications was not a signal to send fewer missionaries but a call for parents and leaders to work with young men to better prepare them for missionary service and to keep them worthy of such service."
Ballard then urged local leaders in all the church's 26,000 congregations to find "at least one more young man, above those already committed, who can be called to serve."
If that happened, "the ranks of our full-time missionaries will swell," Ballard said, "and we will move much closer to our divine mandate to take the gospel to every nation, kindred, tongue, and people."