A Vatican cardinal, Alfonso Lopez Trujillo of Colombia, made headlines last year when he said condoms don't prevent AIDS and may help spread it because they create a false sense of security.
But three months later another cardinal, Godfried Danneels of Belgium, told a Catholic TV program that if an HIV-positive person insists on having sex, "he has to use a condom. Otherwise he will commit a sin" by risking transmission of a potentially fatal virus.
A third cardinal, Javier Lozano Barragan of Mexico, said recently that condoms could sometimes be condoned -- such as when a woman can't refuse her HIV-positive husband's sexual advances -- because preserving her life is paramount. "You can defend yourself with any means," he said.
So just what is the Roman Catholic Church's position? It depends whom you ask. Contrary to what some think, there is no official, authoritative Vatican policy on using condoms to protect against AIDS.
According to several top churchmen and theologians recently interviewed, the issue is being debated within the Vatican and is far from resolution.
The question isn't just an academic or religious one. In areas such as sub-Saharan Africa, hard-hit by AIDS, it's a matter of life and death, and the Vatican is accused by some of failing to come down on the side of life.
The Rev. Angel Rodriguez Luno, professor of moral theology at the Pontifical University of the Holy Cross in Rome, offers two examples to show how complex the question is.
A Catholic cannot discuss condom use with children in school, because "this is inciting them to use them." But if he were a social worker telling prostitutes they risk getting AIDS unless they make their customers use condoms, "I am not doing anything bad. I am lessening the bad."
"But I can't say this in a school. I can't say this in a newspaper," he said. "I must go to the areas where they are and say to them: 'At least do this. You should stop, but at least do this.' "
Over the years, the church has mapped out its opposition to artificial contraception, most famously in the 1968 encyclical Humanae Vitae, or "Of Human Life," in which Pope Paul VI asserted the inseparable link between the unifying and reproductive dimensions of sexual intercourse for husband and wife.
But that document and others deal with using condoms as contraception, not as protection against a potentially fatal virus. The Vatican hasn't issued its most authoritative type of teaching -- an encyclical -- specifically about condoms and AIDS, although it has maintained that abstinence is the best protection.
Yet various cardinals and Vatican offices have made their views known in public discussions and documents over the years, perhaps no one more so than Cardinal Lopez Trujillo, who is president of the Pontifical Council for the Family.
In October, Lopez Trujillo repeated to the BBC his claim that condoms don't help because the HIV virus is small enough to "easily pass through" the condom.
The World Health Organization, among others, said the cardinal's message was dangerous and "totally wrong." The U.N. agency said that condoms are 90 percent effective when used correctly and that the other 10 percent fail because they are used incorrectly.
Dr. Joep Lange, professor of medicine at the University of Amsterdam and president of the International AIDS Society, said in an interview that published medical studies had shown that when one partner is HIV-positive, "consistent condom use is associated with non-transmission."
Lopez Trujillo penned a lengthy defense in December, arguing that because condoms don't offer 100 percent protection, it was misleading and dangerous to speak of "safe sex."
"Safe sex" campaigns were actually increasing promiscuity by giving users a false sense of security, he said.
On another side of the debate sits the Rev. Charles Curran, a Catholic professor of human values at Southern Methodist University who was censured by the Vatican in 1986 for his opposition to church teaching on contraception, among other issues, and barred from teaching theology at the Catholic University of America.
For him, the question boils down to the traditional Catholic understanding of advocating the "lesser of two evils" -- if someone is contemplating killing his neighbor, one could counsel him to instead burn down his barn because that would be the lesser evil.
Janet Smith, head of life ethics at Sacred Heart Major Seminary in Detroit, noted that rape excepted, sex is a voluntary act and there is a 100 percent safe alternative: abstinence.
"A question can be raised about why if you love someone, one would want to engage in an action that might transmit a disease," she said in an interview.
The Bush administration is actively promoting "abstinence-only" education, which urges young people to remain chaste until marriage and excludes any mention of condoms except to depict them as unreliable. Major U.S. medical organizations, as well as researchers at the federal Centers for Disease Control and Prevention, have recommended programs that educate young people about condoms and other contraception, as well about abstinence.
With such differing views, the way churchmen handle the issue comes down to nuance, said Bishop Anthony Fisher, founding director of the Australian branch of the John Paul II Institute for Marriage and Family, which the pope established in 1982 to promote his views on family life.
It may sound hypocritical or confusing, he acknowledged, but there are things you can say privately to someone who comes for pastoral counseling that you can't put in a public education campaign.
When Lopez Trujillo speaks, he is the Vatican's voice to the world and has to promote a simple, consistent message, Fisher said in a recent interview.
"Are individual doctors or clinics giving contrary positions? I think that is going to keep happening," he said.