Andy Sell, 35, Becky, 36, and Finn, 4 say a prayer before dinner Sunday, June 11, 2017. Lauren Justice for The Washington Post

Does prayer affect our intimate relationships? Frank Fincham at Florida State University’s Family Institute, along with several collaborators, has conducted a series of empirical studies of how prayer can impact romantic couples. Fincham wanted to learn whether petitionary prayer—a prayer where you request something—for someone’s partner has any objectively measurable effects on couples. After numerous studies that spanned two decades and published in top journals like “Psychological Science,” the answer appears to be yes.

Praying daily for one’s partner has been linked to numerous positive outcomes: increased relationship satisfaction, greater trust, cooperation, forgiveness and marital commitment. Many of these benefits apply both to the prayer as well as the one being prayed for.

But to experience these benefits, not just any kind of prayer will do—it has to be praying specifically for one’s partner. Of course, prayer can take many forms: ritual, petitionary, colloquial and meditative, among others. The form studied by the researchers was petitionary, making specific requests during prayer. The focus of these prayers was for one’s partner, specifically for divine love, well-being and blessings. (Disclosure: The John Templeton Foundation, where I work, has funded some of Fincham’s studies.)

The positive effect of prayer was measured both in undergraduate, mostly white students in exclusive relationships, as well as African American couples who have been married for many years. To be confident that their findings would be accurate, researchers carefully designed experiments by randomly assigning their participants to treatment and control groups. Differences between the two groups could thereby be attributed to the effects of partner-focused prayer rather than to other factors. The control groups engaged in other activities that could theoretically improve relationships, such as self-focused prayer, self-help books, marriage enrichment programs and positive social interactions with one’s partner. Compared to these control groups, those who prayed for their partners consistently saw the greatest positive impact on their relationship.

In addition to these randomized control trials, Fincham and his collaborators added another feature to strengthen their findings. Social science research often relies on self-reporting, in which participants respond to surveys after engaging in an activity. But what if the participants are mistaken or don’t answer truthfully? To control for these factors, Fincham included third-party observers to watch the behavior of participants before and after testing. The observers found that those who prayed regularly for their spouses experienced better outcomes.

Praying for one’s partner is linked to numerous positive qualities. For example, for couples to thrive, both partners must be willing to make occasional sacrifices. If these sacrifices lead to resentment, the relationship erodes. However, partner-focused prayer caused participants to be more satisfied with the sacrifices they made.

Another set of five studies indicates that partner-focused prayer shifts people toward greater cooperation and forgiveness amid conflict. Forgiveness is not only essential for one’s relationships, but it associated with better physical health, too, so the benefit is amplified. Fincham’s other studies found that partner-focused prayer was associated with greater overall commitment to one’s marriage. This trait was observed both in the person who was regularly praying and the partner who was being prayed for.

The power of petitionary prayer applies not only to romantic partners but to close friends as well. For instance, in experiments with undergraduates, researchers found that those who had been assigned to pray regularly with a close friend showed greater levels of trust, compared to control groups. Multiple studies suggest a causal relationship, not just correlational. Partner-focused prayer apparently causes people to become more satisfied with their marriages. If that is the case, then it is a powerful activity.

Yet how exactly does prayer improve relationships in so many ways? None of these studies presumed that the prayers were being answered by a divine being. Setting aside the possibility of supernatural intervention, research suggests that partner-focused prayer increases selfless love towards one’s partner. It could also help reorient a couple toward long-term shared goals, and away from short-term, adversarial behavior focused on “winning” conflicts.

Partner-focused petitionary prayer could play a role in conflict resolution and marital counseling. While not all counselors will feel comfortable assigning prayer to clients, professionals could certainly partner with congregations and clergy who are committed to fostering healthy relationships.

At this point, Fincham’s findings can’t be applied to all couples. The research needs additional cross-cultural studies. And, these studies were limited to those who already engage in prayer to some degree. Further research could reveal whether prayer also enhances the relationships of couples who do not normally pray.

Fincham’s empirical research, spanning 20 years, appearing in some of the most prestigious psychology journals, has resulted in a consistently reproducible finding: prayer improves marriages. For those who might be curious to try it out for themselves, they could start with the daily one given to the study subjects:

Dear Lord, thank you for all the things that are going well in my life and in my relationship. Please continue to protect and guide my partner, providing strength and direction every day. I know you are the source of all good things. Please bring those good things to my partner and make me a blessing in my partner’s life. Amen.

Thomas Burnett is assistant director of public engagement for the John Templeton Foundation.