The God question
What Prayer Has Cured
Two columns. One lists diseases that vaccines and clean water wiped out or cut by 95 percent or more. The other is empty, and the trials explain why.
The argument
Most believers do not think of prayer and medicine as rivals. The Church urges vaccination, and many members pray for the doctor as well as the patient. This page does not argue with that. It asks a narrower question: when a promise of healing is put to a fair test, what does it do?
The scriptures promise that “the prayer of faith shall save the sick.” Medicine made a smaller promise and kept it in numbers you can count: one disease gone from the earth, others cut by 95 percent or more. When prayer for the sick has been tested in randomized trials, the largest ones found nothing. No disease has been shown to be ended by prayer.
1. The promise
James 5:14–15, King James Version
Is any sick among you? let him call for the elders of the church; and let them pray over him, anointing him with oil in the name of the Lord: And the prayer of faith shall save the sick, and the Lord shall raise him up
This is the passage behind priesthood blessings of the sick.
Read James 5The Doctrine and Covenants repeats the promise and adds a condition: “he that hath faith in me to be healed, and is not appointed unto death, shall be healed” (D&C 42:48). Notice what the condition does. If the person recovers, the promise worked. If the person dies, they were appointed unto death. No outcome can count against it. That is the same shape as the test that cannot produce a no.
2. The column that is full
What vaccines and public health did
Each row is stated as precisely as the record allows. Only one disease is truly gone.
| Disease | What happened |
|---|---|
| Smallpox | Eradicated. WHO declared it gone in 1980; the last natural case was in Somalia in 1977 |
| Polio | Two of the three wild types certified eradicated (2015 and 2019); type 1 still circulates in Afghanistan and Pakistan |
| Diphtheria | US cases fell from about 176,000 a year to 1 in 1998 |
| Measles | Declared eliminated in the US in 2000, and now returning in large outbreaks as vaccination rates fall |
| Whooping cough | US cases down about 96 percent by 1998, though it has since rebounded |
| Tetanus | US cases down about 97 percent by 1998; it can never be eradicated, because the spores live in soil |
| Chickenpox | US cases down more than 97 percent; not eradicated |
| Typhoid | Rare in rich countries, mostly thanks to clean water, sanitation and antibiotics |
Sources: WHO; Global Polio Eradication Initiative; CDC MMWR 1999 and Pinkbook
Add it up and the scale is hard to hold. A 2024 study in The Lancet estimated that vaccination saved 154 million lives worldwide over the last 50 years, 101 million of them babies under a year old (Shattock and colleagues, 2024). That is a model, not a count, and it should be read as an estimate. The authors call vaccination “the single greatest contribution to improved infant survival over the past 50 years.”
Smallpox is worth sitting with. For thousands of years people prayed against it, in every faith, with every sincerity. It killed up to 3 in 10 of the people it infected (WHO). It ended within about a decade of a coordinated worldwide vaccination campaign.
3. The column that is empty
The strongest point on the other side comes first. Two early trials did report a benefit. Among 393 coronary-care patients in 1988, the 192 who were prayed for had a lower severity score than the 201 who were not (Byrd, 1988). In 1999, a study of 990 patients found a small difference on a scoring system the researchers built, though the patients’ length of hospital stay did not differ (Harris and colleagues, 1999).
Then came the largest test. The STEP trial randomized 1,802 heart bypass patients. Among patients who did not know whether they were being prayed for, 52 percent of those who received prayer had complications, against 51 percent of those who did not. The authors’ conclusion: “Intercessory prayer itself had no effect on complication-free recovery” (Benson and colleagues, American Heart Journal, 2006). Patients who were told for certain that strangers were praying for them did slightly worse, 59 percent.
When the Cochrane Collaboration pooled 10 trials and 7,646 patients, it found the results “equivocal,” and said the evidence “does not support a recommendation either in favour or against the use of intercessory prayer” (Roberts and colleagues, 2009). That is the honest summary. Prayer was not proved to do nothing. It was tested, carefully, and did not show up.
Vaccines were tested and the effect was too large to miss. Prayer was tested and the effect was too small to find.
A promise that “the prayer of faith shall save the sick” should not need a statistician to detect.
4. When prayer replaces the doctor
Praying alongside treatment harms no one. Praying instead of treatment is different. A 1998 study in Pediatrics reviewed 172 American children who died after their parents relied on faith healing in place of medical care. It found that 140 of them had conditions with survival rates above 90 percent under ordinary treatment (Asser and Swan, 1998). The Church teaches the opposite of what those families did. But the study shows what happens when faith healing is used instead of medicine.
What is true on the other side
- The Church sides with medicine. In August 2021 the First Presidency wrote: “we urge individuals to be vaccinated. Available vaccines have proven to be both safe and effective” (KSL). That was the right call, and it should be said plainly.
- Scripture makes room for care. Those who lack faith to be healed “shall be nourished with all tenderness, with herbs and mild food” (D&C 42:43), and Colossians calls Luke “the beloved physician” (Colossians 4:14).
- A God who is free cannot be put in a trial. The Bible says “Thou shalt not tempt the Lord thy God” (Matthew 4:7), and many believers hold that God does not perform on request.
The common rebuttals
“God works through doctors. The vaccine is the answer to the prayer.”
That may be how it feels from the inside. But look at what it requires. Prayers were offered against smallpox for thousands of years, and the answer arrived only when a vaccine was paired with a worldwide campaign. If the answer always comes in the form of medicine, and never without it, then medicine is doing the work you can measure. The prayer is a way of giving thanks for it.
“You cannot test God.”
The scripture made the claim first. “The prayer of faith shall save the sick” is a statement about sick people, and sick people can be counted. The tests did not invent a promise to check. They checked the one in the text.
“I have seen a healing myself.”
Many illnesses get better on their own, and people tend to pray hardest when things are worst, so recoveries follow prayers often even if prayer does nothing. That is exactly why trials compare a group that was prayed for with a group that was not. When that comparison was made, the difference disappeared.
What this means
Every disease on the list fell to something that could be tested, measured, and given to everyone. No disease has ever been shown to fall to prayer, though the other column has been open for all of human history.