Keywords

The study of virtue is central to positive psychology, and it has also received substantial scholarly attention in the psychology of religion/spirituality (R/S). To gain a richer understanding of virtues, any theoretical approach must account for religious/spiritual contexts (Snow, 2019). Virtues involve acting in aspirational ways, often in the face of contextual pressures that make doing so difficult, and religious traditions can influence how people understand and practice virtues in their relationships, families, schools, workplaces, and communities (VanderWeele, 2017; see Ratchford et al., Chap. 4, this volume). For example, Saroglou (2011) contends that one of the central features of religion is to shape moral behaviors by prescribing virtuous actions and proscribing immoral ones. For example, religious communities may endorse virtues with social norms and a meaning system that encourages people to live virtuously, while also providing them social support to persist in acting virtuously even when it is difficult.

A limitation of prior work in positive psychology is that scholars often focus on one virtue at a time without considering how virtues may compliment or interact with each other in the context of relationships and group interactions (Davis, 2019). Some scholars (e.g., Emmons, 2016; Lavelock et al., 2017) consider humility and gratitude to be interrelated, superordinate relational virtues. As such, these twin virtues provide the cognitive and motivational structure to support a variety of other virtuous behaviors. Therefore, the purpose of this chapter is to provide a focused review of research on R/S and the virtues of humility and gratitude. First, we define terms and review our key research questions. Second, we describe the method of our search and review evidence pertaining to our primary research questions. Finally, we discuss limitations, directions for future research, and implications for clinical practice and religious communities.

Definitions

Religion and spirituality (R/S) have been defined in various ways. Spirituality has been defined as a “search for or relationship with the sacred” (Harris et al., 2018, p. 1). People may practice spirituality within or outside the context of a formal religious community, and they may seek greater spiritual connection with various sources of sacredness, including God, nature, humanity, or the transcendent (Davis et al., 2015). Religiousness has been defined as “ritual, institutional, or codified spirituality, which is culturally sanctioned” (Harris et al., 2018, p. 1).

Both spirituality and religion can be understood as relational and cultural constructs. Accordingly, people’s relationships and cultural background influence how they understand and seek connection with whatever they perceive as sacred. According to Saroglou (2011), R/S has four main functions: believing, bonding, behaving, and belonging. An important aspect of how individuals relate to whatever they perceive as sacred is how people understand what kind of life is worth pursuing (i.e., beliefs), and these belief systems often include notions of virtue (i.e., culturally esteemed and prescribed ways of thinking, feeling, and behaving). Relational virtues, such as gratitude and humility, involve people’s way of understanding how they ought to form, maintain, and repair relationships with other people and with perceived sacred entities (Sandage et al., 2020).

Humility is a multidimensional construct that (a) intrapersonally involves having an accurate view of one’s strengths and limitations and (b) interpersonally involves being other-oriented rather than self-focused (McElroy-Heltzel et al., 2019). In addition to regulating negative interpersonal behaviors in alignment with modesty norms, some define humility as involving an orientation toward the betterment of relationships (e.g., Hook et al., 2013). Behaviors that indicate humility may vary by context (Davis et al., 2016). For example, in a qualitative study of leaders, Owens and Hekman (2012) found evidence that humility is behaviorally expressed in three main ways: (a) acknowledging mistakes and limitations, (b) exhibiting teachability, and (c) appreciating the contributions of others.

The latter behavior points to an overlap between humility and gratitude. Gratitude is a positive emotion that occurs when people recognize that another being (a human, animal, or divine being) has intentionally done something to benefit them. Gratitude has been studied as a state, mood, or disposition (Ma et al., 2017), but to date, most studies have conceptualized and assessed it as a disposition—the tendency to feel gratitude across a range of situations, contexts, and relationships. The more people perceive a gift as good, unobligated, and costly, the more gratitude they feel (McCullough et al., 2001). In contrast, people high in entitlement may tend to overlook the contributions of others or view positive acts as obligations rather than gifts (Navarro & Tudge, 2020). Thus, low humility often may lead to ingratitude, which then undermines trust and cooperation (Emmons, 2016). In contrast, a stance of viewing all things in life as spiritual gifts that find their ultimate source in sacred entities (e.g., God or nature) may provide religious/spiritual individuals with a persistent sense of gratitude that curbs entitlement.

Key Research Questions for Review

We had two key research questions that organized this chapter’s review. The first research question was whether and how R/S are related to the virtues of humility and gratitude? This question is important given debates on whether R/S causes greater prosociality (Galen, 2012). Religious communities define and seek to promote virtuous behavior (Saroglou, 2011), but do they succeed? There is meta-analytic evidence that religiousness is weakly correlated with self-enhancement and social desirability bias (Sedikides & Gebauer, 2010). People high in religiousness may think of themselves as virtuous, but they may not actually be much more virtuous than people who are lower in religiousness (Davis et al., 2013). Therefore, an initial place to start is to compare correlations of R/S with humility and gratitude, followed by looking for any evidence regarding causal direction or important moderators.

The second research question was based on the social oil hypothesis of humility. Prior theory on humility suggests that humility is especially important in contexts that involve a potential for conflict, such as power struggles, intellectual disagreements, or cultural differences (Van Tongeren et al., 2019). According to the social oil hypothesis, humility “reduces relational wear and tear in situations in which conflict is highly likely or there is a substantial power differential between partners. Namely, [this hypothesis] predicts that consistently expressing humble behaviors will buffer a relationship from deterioration in relationship quality that often accompanies competitive traits or conflict” (Van Tongeren et al., 2019, p. 464). Furthermore, even when offenses occur, humility may also promote relational-repair behaviors.

For several reasons, religious communities and contexts are important places to study the social oil hypothesis. First, they often involve some degree of tradition or hierarchy (Worthington, 1988). Second, they not only seek to promote commitment to ideological beliefs, but these beliefs are often sanctified, which has the potential to intensify group dynamics (Graham & Haidt, 2010). Third, given that religious groups have strong traditions that promote conformity and cohesion, belonging to a religious group may create a potential for conflict, both within the community and with outsiders. Sanctification of religious ideas may result in both benefits (e.g., cohesion, belonging, and meaning) and costs (e.g., outgroup derogation, prejudice, and interpersonal conflict; for a review, see Hall et al., 2010). To the degree that religious groups promote humility (and perhaps gratitude) as a virtue for guiding divine and human relationships, it may help them optimize the benefits and costs of ideological commitment.

Although this second question was primarily focused on R/S and humility, we scoured the literature on R/S and gratitude for clues about how gratitude and humility might work together to help people navigate relationships and manage conflict. If gratitude and humility are conceptually interrelated, then practicing gratitude might be an important way for people to express humility in their relationships. The find-remind-bind theory of gratitude (Algoe, 2012) overlaps with theorizing on the role of humility in strengthening and repairing social bonds (Davis et al., 2013). In particular, relational offenses may undermine trust and deter cooperation, but when offended people turn their mind toward the benefits they receive in a relationship with their perceived offender, this altered focus might provide motivation to continue investing in the relationship. In research on couples, gratitude can help protect marriages from deterioration due to conflict (Fincham & Beach, 2010). Likewise, in some forgiveness interventions, participants learn to engage gratitude as an other-oriented emotion that helps increase emotional forgiveness (Wade et al., 2014). On the other hand, some evidence suggests the benefits of gratitude may require mutual investment and can have drawbacks when only one partner practices gratitude with a partner who is low in gratitude (McNulty & Dugas, 2019). Thus, we looked for potential inroads for studying gratitude as a hidden factor in the social oil hypothesis of humility. Because this area of the literature is early in its development and therefore somewhat sparse, we ultimately will explore future directions that may help illuminate this association further.

Method of the Search

On December 4, 2020, we conducted searches of PsycINFO that included the following search terms: relig* AND gratitude, God AND gratitude, gratitude to God, relig* AND humility. This search resulted in 367 abstracts for the search on humility and 427 for the search on gratitude. We included articles that were published in a peer-reviewed journal and included at least one measure of R/S and one measure of humility or gratitude. We identified 62 studies that focused on humility and R/S and 32 studies that focused on gratitude and R/S.

Results

Overview of Samples and Research Designs

A summary of the results is presented in Appendix 24.S1 (see Tables 24.S1 through 24.S4). For studies on humility, the vast majority (k = 47) involved convenience samples of undergraduate/graduate students or MTurk/Qualtrics-Panels workers. The remaining studies (k = 15) recruited other types of samples, including general community samples or specific population samples (e.g., religious leaders, mental health practitioners, psychotherapy patients, married couples, organizational employees). Most studies recruited U.S. samples (k = 48), but 14 studies recruited from samples in other countries (e.g., Iran, Pakistan, Malaysia, Poland, Romania, Canada, and New Zealand). Most studies (k = 53) used a cross-sectional/correlational design; however, nine used an experimental design, longitudinal design, or both (ks = 4, 4, and 1, respectively).

For the gratitude studies, nearly half the studies recruited convenience samples of undergraduate or graduate student participants (k = 14), and the remaining studies recruited general community samples (k = 12; e.g., of adults, older adults, or youth) or special population community samples (k = 6; e.g., married couples, adults with recurrent depression, or adults with heart failure). Most studies involved U.S. samples (k = 21), but 11 studies recruited samples in other countries (e.g., Iran, Taiwan, China, India, Vietnam, Poland, Australia, and the United Kingdom). Most studies used a cross-sectional/correlational design (k = 28), but three studies used a longitudinal design, and one additional study used an experimental and longitudinal design.

Overview of Measures

The vast majority of studies in the current review relied on self-report measures of trait (i.e., dispositional) humility or trait gratitude. Several studies also measured gratitude to God, and a few of these studies (e.g., Lin, 2014, 2017) conceptualized dispositional gratitude as a higher-order construct that included gratitude to God.

R/S and its Association with Humility and Gratitude

Supplemental Tables 24.S1 and 24.S2 provide an overview of studies and correlations between R/S and humility. Correlations between R/S and humility ranged from strongly negative to strongly positive (the mean correlation was .18, and median was .21). Measurement moderators are often helpful for making sense of such disparate findings. For example, when correlations were negative, R/S was often assessed with a measure of religious orientation or of negatively valenced religiousness/spirituality (e.g., religious/spiritual struggles, religious ethnocentricism, or anger toward God). In addition, it is important to consider the conceptual difference between self-reports of humility (which tend to be relatively stable over time) and other reports of humility within a specific relationship (which may change quite a bit after major events such as betrayals or after noticeably self-sacrificial behaviors; Davis et al., 2016).

Supplemental Tables 24.S3 and 24.S4 provide an overview of studies and correlations between R/S and gratitude. Again, correlations ranged from weakly negative to strongly positive, with an average correlation that was weakly to moderately positive (the mean correlation was .27 and median was .25). As before, measurement moderators will likely help understand this wide variability in correlations. For example, because gratitude is an emotional construct, it likely is related quite strongly to emotional and relational facets of R/S (e.g., spiritual transcendence), which is what Table 24.S4 suggests. Table 24.S4 also suggests that if R/S was assessed as a measure of religious/spiritual well-being (which some have critiqued as conflated with psychological well-being; Finke & Bader, 2017), the R/S–gratitude link tended to be stronger.

Across both literatures, an important question involves the need to explore the causal direction of the association between R/S and virtue. Several research groups have proposed models that situate R/S and virtue in a causal chain, and most situate R/S engagement in a faith community as leading to greater virtue (e.g., Krause et al., 2014). These studies have yet to use designs that would support an inference of mediation—and recently, scientists have become increasingly critical of correlational, cross-sectional tests of mediation (Maxwell & Cole, 2007). Thus, at this point, although various theories exist for the causal association between R/S and humility—and some studies have taken strides in a promising direction (e.g., using an experience sampling method; Olson et al., 2018)—these ideas have yet to be put to an adequate test.

In sum, we see evidence that humility and gratitude tend to correlate with measures of trait-based R/S, but correlations vary widely when R/S is assessed as part of a coping process. There is very limited empirical data to test causal theories about how R/S relates to these twin virtues of humility and gratitude. Most studies involved monomethod bias, which does little to allay critiques that R/S correlates with virtue due to social desirability bias (de Vries et al., 2014).

The Social Oil Hypothesis

Our second research question involved exploring evidence for the social oil hypothesis of humility. In particular, we hoped to explore potential inroads for examining how humility and gratitude may work in tandem to protect relationships from potential conflict. First, to the degree that humility functions to reduce the potential for religious conflict, we might expect it to correlate with other measures of religious tolerance or openness; indeed, that is what an inspection of Table 24.S2 generally reveals. For example, Davis et al. (2016) found that general humility and intellectual humility were negatively related to religious ethnocentrism (r = −.28 and −39, respectively). Similarly, Krumrei-Mancuso and Newman (2020) found evidence that intellectual humility buffers the association between political orientation and religious polarization in a sample of MTurk workers (N = 587), but only among political conservatives.

Despite the potential benefits of humility for managing potential conflict, Zhang et al. (2018) tested a theory that humility in the religious domain may involve an existential tradeoff. Across two studies, they found that people assigned to imagine themselves in an ideologically dissimilar small group tended to feel reduced social belonging and meaning in life, but people who were higher in intellectual humility experienced this effect to a lesser extent.

Only one study has tested the social oil hypothesis through inducing humility after an in vivo offense. In Van Tongeren and Stafford et al. (2016b), Christian participants shared their views on a contentious topic with a religious outgroup member. After purportedly receiving negative feedback from the outgroup member, participants completed a word-sorting task that was used to prime humility. Unknown to participants, words (humility or non-humility) flashed on the screen too quickly to be processed consciously. Finally, participants had a chance to retaliate against the outgroup member. They prepared a snack for the critic, and the dependent variable was the amount of hot sauce used in preparing that snack. As expected, people in the humility condition doled out less sauce (i.e., acted less aggressively) than people in the control condition, despite having received equivalent explicit ratings of negative feedback from the outgroup member.

We hoped to find studies exploring how gratitude and humility might work together to protect relationships from potential conflict, given prior theory linking the two virtues. One study of couples examined relationship satisfaction and gratitude to God for one’s partner, but that study did not assess humility (Fincham & May, 2021). Additional work is needed to test how humility and gratitude may play complimentary roles in protecting relationships from conflict. For example, in prior work by Fincham’s lab, couples were trained to pray for the benefit of their partner (Fincham & Beach, 2010). A next step might be to teach couples to pray for increased gratitude for their relationship. Sanctification of gratitude through prayer might amplify the power of typical gratitude interventions (Schnitker & Richardson, 2019). Furthermore, based on our theorizing, partners who know their partner is regularly thanking God for their relationship ought to see each other as humbler, which ought to lead to positive relationship outcomes (e.g., higher relationship commitment, trust, and satisfaction).

Taken together, we found additional programmatic work on the social oil hypothesis of humility. Although humility may reduce the potential for conflict, it could also reduce the potential for a sense of solidarity and shared sense of meaning in life. Based on prior theory, we suspect that gratitude plays an important role in helping people practice and express humility in the context of conflict, but these possibilities need rigorous empirical testing.

Discussion

In the current chapter, we framed humility and gratitude as twin relational virtues. The purpose of our review was to examine two questions about R/S and virtues while examining findings from both literatures—the R/S–humility literature and the R/S–gratitude literature. First, to what degree are religious/spiritual constructs associated with each virtue? Second, to what degree do we see evidence that these virtues may function as a social oil within the context of relationships, especially given that commitment to R/S can sometimes amplify conflict?

Our review yielded ample evidence of association between R/S and the two relational virtues. At this point, most research is based on cross-sectional, correlational designs, despite provocative theories that suggest engaging in religious communities may increase gratitude and humility, which in turn can promote better relationships and positive outcomes. These ideas certainly fit into larger theories attempting to explain the ways that religious involvement may promote better health and mental health (VanderWeele, 2017; see also Wang et al., Chap. 29, this volume). The field seems ripe for rigorously testing theories about how R/S may influence changes in gratitude and humility, as well as in other outcome variables of interest.

Regarding the social oil hypothesis, some recent work on humility supports prior theorizing. Prior research shows that R/S can sometimes increase conflict, especially when people imbue their point of view with sacred meaning. Although some initial evidence suggests that humility is sometimes associated with religious openness or tolerance, our review found evidence that humility may involve a tradeoff between existential security (which gives greater meaning and belonging) and ideological span (which may reduce conflict). Prior work on quest religious orientation has found a similar pattern in which greater ideological openness and willingness to explore existential ideas may come at a cost to psychological well-being (Van Tongeren et al., 2016a, b).

Although we found additional support for the social oil hypothesis, some recent findings raised new questions. For example, humility may work somewhat differently in politically conservative people than it does in politically liberal people. As eager as we may be to explore this unresolved issue, it may require careful and programmatic work. For example, moral values may affect how people understand humility—conservatives may emphasize respect for authority and tradition, whereas liberals may emphasize egalitarian structures (Davis & Hook, 2019). Also, for some highly religious individuals, humility may involve a dependence on God, which within some traditions may be understood as viewing beliefs through the lens of scripture (Hill et al., 2018).

A glaring gap in these two fields is the need for more studies that test causal theories of how R/S may promote greater virtue. Given overlap in theory on humility and gratitude, we hoped to find more research on the social oil hypothesis at the intersection of R/S, humility, and gratitude. At this point, we found very little, but it was easy to see promising next steps. For example, although there is limited work manipulating humility experimentally, many strategies exist for helping people to practice gratitude.

Limitations and Future Research

The current review revealed several limitations in the existing literature on R/S, humility, and gratitude. Samples included mostly undergraduates or people from crowdsourced platforms, and most measures were self-reports, raising concerns about monomethod bias and social desirability. More studies are needed that recruit samples from diverse faith traditions and ideally from a variety of nations, to avoid conflating nation and religion (Vishkin et al., 2020).

Although some studies proposed conceptual models relating R/S with humility or gratitude, the field is currently plagued by problems associated with cross-sectional data. The field needs more programmatic work focused on debates at the intersection of positive psychology and the psychology of R/S. When and how does R/S promote prosociality or flourishing? To answer such questions, future work could draw on current theories of how flourishing occurs across the lifespan (Seligman, 2018) and draws support from key systems, including family, work, educational, and religious communities (VanderWeele, 2017). Under ideal circumstances, how do parents instill relational virtues through aligning these four systems to promote virtuous habits (Obeldobel & Kerns, 2021)? Similar ideas are explored in further detail in Chap. 17 (King et al., this volume). These authors discuss how self-transcendent emotions (including gratitude), which are encouraged and engaged in religious/spiritual contexts, may increase meaning making and thriving in youth and adolescents. The Positive Religious and Spiritual Development theory introduced in Chap. 18 (Davis et al., this volume) serves as an integrative theory that—through its applications across life stages, contexts, and cultures—may be useful for addressing such questions by attending to both R/S and positive psychology.

To answer such questions, scholars can continue to build on theory about how humility and gratitude function within interpersonal relationships, such as work on how observing others express gratitude can strengthen groups (Algoe et al., 2020) or how gratitude can protect relationships from envy, cynicism, or other relational threats (Solom et al., 2017). Given that gratitude is such a powerful motivator of prosocial behavior (Ma et al., 2017), what virtues set the stage for gratitude? Furthermore, although most studies in our review focused on individuals, an important next step is to test theories about gratitude within groups. Recent work suggests that gratitude may cause greater conformity to social norms (Ng et al., 2017) and may alert people to the value of relationships (Williams & Bartlett, 2015). Based on recent theory on transcendent emotions (Stellar et al., 2017), it may be important to explore how religious communities use collective experiences of awe, which may help groups bond, promote humility, and set the stage for coordination of other prosocial acts. This shift to studying gratitude in groups also has the potential to address cultural critiques of positive psychology (Wong, 2019).

Given the need to test causal theories, we suggest more studies use intervention or intervention-like designs to test process models of how humility and gratitude may work in tandem. Perhaps studying how various faith traditions practice gratitude may reveal new ideas on how to amplify the currently small effects of gratitude interventions (Cregg & Cheavens, 2021). Given the minimal intervention work on humility, it may be helpful to develop a theoretical model that situates humility as a higher-order virtue that involves the practice of other virtues in key situations, such as generosity in the face of scarcity, forgiveness after offenses, and gratitude to counter the tendency for negative thoughts to narrow one’s attentional focus.

Practical Implications

What are this chapter’s implications for practitioners? Table 24.S5 (in Appendix 24.S1) presents humility (k = 2) and gratitude (k = 2) intervention studies that can be used by practitioners or religious leaders within their target populations. The table explores how each virtue is engaged, the intervention that was used, and the empirical findings.

In studies of clinicians, humility has been linked with social justice commitment, intercultural competence, and faith maturity (Bell et al., 2017). In clinical consultation groups focused on discussion of R/S issues, humility has been correlated with self-efficacy, emotional maturity, and positive attitudes toward addressing R/S in psychotherapy (Crabtree et al., 2020). Humility has also been linked with positive qualities in clergy. For example, in a study of pastors, exposure to religious diversity correlated to religious tolerance, and this association was stronger in those higher in intellectual humility (Hook et al., 2017). Similarly, in a study of Christian leaders, intellectual humility was related to a variety of indicators of willingness to collaborate with mental health professionals, as well as with emotional intelligence (Hodge et al., 2020). Humility interventions—such as workbooks and workshops—have shown further promise within populations of religious leaders, with evidence that they may improve awareness of one’s own level of humility (Cuthbert et al., 2018) and might lead to changes in one’s humility, especially for people with a secure attachment relationship with God (Jankowski et al., 2021).

Theory and research on gratitude suggests that attending to gifts and expressing gratitude are powerful ways to avoid the potential for negative rumination to cause a downward cycle. Based on Brad Owens’s work on leaders (e.g., Owens & Hekman, 2012), noticing and appreciating the contributions of others in a group or community is one of the telltale signs of humility in leaders. We also know from research on couples that negativity can cause negative cycles of thoughts, emotions, and behaviors, whereas gratitude and its expression help keep relationships healthy (Fincham & May, 2021). Even when people lack motivation to act virtuously, practicing gratitude is a good step, because it enhances motivation to act prosocially. Although gratitude plays this role in all relationships, people in religious communities may have unique resources to amplify gratitude (Krause & Ellison, 2009). Additionally, individuals within religious communities can draw on religious/spiritual teachings and traditions to reinforce and sanctify the importance of gratitude and can interlace rituals with experiences of gratitude (Schnitker & Richardson, 2019). When people enjoy the benefits of a strong community, gratitude has the potential to build on itself via cycles of reciprocity.

Conclusion

Although many studies on R/S and humility and gratitude have been conducted, from the present review, we see clearly that there is a need for programmatic work testing theory on how humility and gratitude complement each other within religious/spiritual individuals and communities. In this chapter, we have called for more work that explicitly asks people to practice humility or gratitude and explores ways of engaging religious/spiritual beliefs or practices to amplify virtuous behaviors. This work has the potential to improve our understanding how of R/S affects physical and mental health through strengthening relationships in families and communities. It also has the potential to help scientists and practitioners understand how relational virtues allow R/S communities to balance tradeoffs associated ideological commitment and belonging. Going forward, there is a need for both stronger theories and stronger methodologies that test the causal implications of said theories, as well as for work that explores humility and gratitude practices within a chain that causally links religious/spiritual constructs with positive outcomes.