1This book has explored the role of biblical interpretation in exhortations to higher fecundity by U.S. Protestants. Earlier critics of natalist exegetes have regarded contraception as the central issue of interest, and emphasized the difference between rejection of family planning (portrayed as problematic legalism) and planning a large family (portrayed as one reasonable application of a Christian model of parenthood). They have rarely critiqued natalism per se. From my perspective, the anti-contraceptive ideology is separate in theory and peripheral in practice since large families can be planned. All natalists use similar arguments for high fecundity, based on the same Bible verses, regardless of whether they allow contraception or not.

2Luther’s ideas about marriage and family have been much studied, but little attention has been given to his thoughts on human fertility and the Old Testament fruitful verses except by Yegerlehner, and by the natalist writers Provan and Carlson. This is the first study to test natalist appropriation of Luther’s words against their immediate literary context, his pastoral and theological concerns, and 16th-century demography. Natalists claim that Luther taught a reproductive law of nature, but I have shown this to be rhetorical hyperbole responding to crises of the 1520s, including Luther’s battle with vowed celibacy; a different idea can be found elsewhere in his writings. Furthermore, his short temporal horizon was incompatible with natalist demographic ambitions. On the other hand, Luther’s presentation of parenthood as a penitential discipline offers support to the natalist idea that the trials of child-rearing form parents in Christian character, although this has not been noted by natalists.

3Biblical scholars comment on all the fruitful verses, and historians of ancient Israel discuss fertility and population in that culture. By undertaking a systematic evaluation of each natalist argument using recent Old Testament scholarship, this book has challenged some attempts by Old Testament scholars to apply the fruitful verses to contemporary Christians. I have demonstrated that while ideas about fecundity as a material blessing to parents and the nation echo ancient Near Eastern culture and are plausible as original meanings of the fruitful verses, the Old Testament writers regarded offspring as a reward, and so the verses should be read as promises, not exhortations. Further, an Old Testament theology drawing on the wider canon relativizes fecundity by identifying it as only one aspect of a broader divine plan, and subordinated to holiness.

4Augustine’s thoughts on human reproduction have been intensively researched with reference to theological topics such as original sin, and to various modern issues including gender and sexuality. However, researchers interested in fertility or population have, because of the widespread conflation of anti-contraception and natalism, often regarded his legacy as part of the problem. In order to refute natalist arguments, I undertook the first ressourcement from Augustine’s writings directed against natalism. This approach challenged recent scholarly efforts to portray Augustine as pro-reproductive by highlighting his insistence that the church is built by the Word and regenerated by the Spirit, not by reproduction. Moreover, Augustine reminds us that although secular social preservation is a good, the ultimate future of humankind is assured by the general resurrection of the dead. My study of Augustine’s writings also underlined his belief that spiritual blessings are more important than parenthood, and his concern that pursuit of what is good should not lead to loss of what is better.

5Ecological hermeneutics have been applied to many parts of the Bible, but only briefly to the fruitful verses, for example by Lohfink, DeWitt, and Bratton. Taking U.S. demographic exceptionalism as the primary context for my analysis, this book has offered an innovative development of previous work, countering specific natalist interpretations with an eco-biblical hermeneutic. This ecological approach suggests that natalism would only be appropriate in special circumstances: if a too rapid shrinkage of the population became detrimental to welfare, or if it were necessary to avoid the extinction of the human species. At present there is no prospect of either circumstance arising on a global level, or nationally in the U.S. or UK.

Possible directions for further research

6Social-scientific research on U.S. natalism is needed to provide data on the number of people affected, the degree of influence, and their geographical distribution.1 Some questions posed by Goodson in her 1996 survey of Protestant seminaries (including her three alternative interpretations of “be fruitful and multiply”) could be repeated to allow comparison. The commonly used measure of belief in inerrancy is rather indirect, so a better and more specific measure of how strongly behavior is shaped by the Bible is needed. To link this with natalism, further questions would be needed to uncover views about ideal family size and how far they is governed by biblical norms and prescriptions, or only by personal preference. A similar survey in the UK would also be helpful.

7Case studies of natalism within a congregation would be helpful in clarifying the relative importance of internal and external influence, from peers and teaching, from sermons, books, and other media. This could be done in one of the groups with a significant natalist presence: the Presbyterian Church of America (PCA, a 1970s conservative splinter from mainline Presbyterians), the Lutheran Church Missouri Synod (LCMS, a Southern branch of Lutheranism), or the SBC.2 Anthropological research could investigate questions beyond those used in national surveys, such as whether leaders and laity differ. Whereas natalist Old Testament reception is minimal in published Catholic sources, there is evidence of Catholic natalism, and further investigation would be desirable.

8The association of natalism with ideas about gender could be investigated. A minority among natalists affirm views which Kathryn Joyce labels patriarchal, for example emphasizing the wife’s submission to her husband. Other natalists, while distancing themselves from patriarchy, are not egalitarian with regard to gender roles. A review of Joyce’s book by Nathan Finn criticizes her for using the word “complementarian” to describe the Quiverfull movement.3 Finn emphasizes the difference between “oppressive patriarchy,” which is “an extreme fringe” linked with “far-right aberrations,” and a biblical complementarian viewpoint which he affirms (48). Finn himself seems not to be natalist, but his review suggests another fracture in natalism: between complementarians and patriarchs.

9With regard to further historical ressourcement, the writings of John Calvin should be prioritized. Though he is far less significant in the reception history of the fruitful verses than Martin Luther, many natalists (of both limited and unlimited types) express an affinity with historic Puritans and can be regarded as part of the New Calvinist movement which esteems his writings. Kathryn Blanchard has explored Calvin’s ideas about contraception, but research is needed on his exegesis of the fruitful verses and on what views, if any, he expressed about human fecundity. Another avenue of research from historical sources would be a comprehensive study of Christian reception of the metaphors (grass, dust, stars) that were used in the Old Testament to signify numerous offspring.

10The paradox of those natalists who are also ecologically concerned deserves further attention. While some natalists are cornucopian, others are not. For example, Mary Pride blames consumerism for ecological damage. A striking example is John Jefferson Davis, who teaches natalism and environmental ethics in different parts of the same book (Ethics 63-67, 263-73). Also, in an article surveying recent works of systematic theology, he critiques “ecological blind spots” where they fail to consider God’s care for the earth (Davis, “Ecological”). This reflects a wider phenomenon discussed in chapter 6: the refusal to treat population size as a factor in ecological sustainability. A closer look at other writings by natalists to identify ecofriendly interpretations of other Scriptures, and statements about environmental issues, would be helpful. The surveys suggested above could include questions on environmental attitudes for this comparative purpose.

Prospects, and value of the research

11The scenarios predicted by Eric Kaufmann and others suggest that religious groups practising an “endogenous growth model” will change the U.S. population’s character. If trends persist, by the end of this century the nation be dominated by those Christians, Mormons, and others who have a large-but-limited approach to family size. After another century, however, they in turn would be dwarfed by Quiverfull adherents and others practising unlimited fecundity. More importantly from an ecological perspective, the total U.S. population would rise above one billion.4 The consequent decline in average individual economic welfare would eventually cause reduced fecundity, except among the most “ascetic” natalists, but is there hope for a change in trajectory before that happens? Sectarian techniques such as religious schools and home education do enable retention of most offspring in membership (Kaufmann 27), and “most” is enough for demographic effects. It is not even necessary that children be retained by the particular sect of their birth, only that natalist ideology is transmitted and acted on.

12Is there any hope that these scenarios for U.S. population growth will not occur? Extrapolation from the current high fertility of some fundamentalist groups many decades into the future is not a reliable predictor. Many U.S. adults are moving away from Protestant fundamentalism. A transition matrix using GSS data to explore how U.S. citizens changed their religious affiliation after age 16 found that “Protestant Fundamentalists” (a category that includes Missouri Synod Lutherans, “Conservative” Evangelicals, and many types of Pentecostal, according to GSS Methodological Report 43) have a negative-3.3 net flow: fewer convert than leave (Skirbekk, Kaufmann, and Goujon 300). By contrast, the “Protestant Moderates” (which include “Open” Evangelicals) have a positive + 10.3 net flow. The fundamentalist churches are unattractive to adults, but their birth rate is higher: though they “lose” more children, they have more to spare and so they can keep increasing despite their losses. However, the endogenous strategy is not reliable in a U.S. context: 44% of Americans “do not currently belong to their childhood faith” (Pew 1). The extrapolators need to remember that religion is more like a voluntary affiliation than a genetic ethnicity.

13The widespread cultural and legal assumption that babies by default belong to the parents’ (or in some cultures specifically the father’s) religion is a mainstay of endogenous growth strategies. Social scientists collude in this when they use the term “apostate” to describe anyone who chooses a different religion from the religion of his or her father. The trend of fundamentalist population growth might be slowed by a legal extension of children’s rights to end that presumption. It could entail the regulation of religious curricula in private schools and among homeschoolers. However, such a change is not politically feasible. Other kinds of intervention are unlikely to be effective. If the financial incentives to additional reproduction were reduced (for example, through cutting tax credits after the second child, while mitigating socially regressive side-effects by redirecting the funds to state schools) that might lower birth rates among some types of recipient (Brewer, Ratcliffe, and Smith 245). However, since religious natalists are self-sacrificing in pursuing their perceived duty, they would be less influenced than others. Even if a reduction in state subsidies lowered birth rates overall, it would probably widen the gap between fundamentalists’ and others’ fertility.

14A change in hearts and minds is the best way forward. The journey of individual members, and perhaps of whole congregations, away from fundamentalism and toward mainline historic Christianity is desirable. However, there will be large numbers of fundamentalists in the U.S. for the forseeable future, so a way to help them feel comfortable about choosing smaller family sizes has to be found. If some fundamentalists chose to redirect their energy away from biological fecundity and toward other pursuits such as evangelism and mission (including social concern and creation-care), that would be good for ecological sustainability. One contribution to this would be non-natalist interpretation of the Old Testament fruitful verses that is nevertheless compatible with fundamentalist approaches to the Bible. This book is one more step in that direction, but although more research should be done, a far more important task is popular outreach by non-natalists within each denomination to fellow members of their churches, especially to young people.

15There is much potential for immediate and enduring reductions in our ecological impact through lower fertility, given the high U.S. per capita ecological footprint of 7.0 gha (GFN) and the long-term consequences of additional births (Murtagh and Schlax 18). Ecological impact is a product of impact per person multiplied by population size (which is driven by birth rates). And yet while many researchers and activists labor toward reducing the impact per person (which is good and essential because even if the population stabilized, lower-impact living would be needed), often through small efficiency gains, few consider the large and rapid savings achievable through lower fertility. Looking beyond the U.S., there are many types of natalism, including state, religious, and cultural natalisms. If young people were liberated from all natalist pressures and allowed to follow their own inclinations, there would be lower birth rates and less ecological impact. And it is not all-or-nothing: if just one couple influenced by natalism is released from that ideology and has a smaller family, they will personally avoid “many troubles” (1 Corinthians 7:28, NIV) and also help mend the world.