In chapter three of Doing Faith Justice, Fred Kammer refers to modern Catholic social teaching (CST) as “our best kept secret.” Among American Catholics, at least, this strand of Catholic tradition is not well known and generally underappreciated. Many weekly Mass-goers have a decent grasp of creedal theology and are also well acquainted with the Church’s teachings in the area of sexual morality, but when it comes to social concerns, too often Catholics allow the dominant framework of American electoral politics to set the terms of the conversation. Kammer’s book, now in its fourth edition, was written with the intention of spreading the word about CST, which has been the focus of his scholarly research throughout his career. On the whole, the book is an excellent resource: it’s sufficiently accessible so as to serve as an introduction for those who are first getting into the topic, but also has enough depth to hold the attention of trained theologians. Those who own an earlier version of the work may still want to purchase this fourth edition, which integrates the writings of Popes Benedict XVI and Francis, and also includes updated social and economic analysis.

The driving force behind the book’s argument is the conviction that, “The God of Biblical revelation is known through interhuman justice” (quoted on p. 22). Kammer appropriates this idea from the work of Peruvian theologian Gustavo Gutiérrez, who adds: “When justice does not exist, God is not known; God is absent” (ibid.). We ignore this truth at our own risk, as Scripture also makes clear that divine judgment is reserved for those who refuse to care for the poor. While Kammer frames this judgment as destruction that the community brings upon itself, however one understands it, the basic point still holds true: When the people of God “rel[y] on the wisdom of their own schemes and clever treaties, and not on the Lord,” destruction inevitably follows (p. 30). The central message of the Old Testament prophets, Kammer points out, was “you have forgotten the poor” (ibid.). At different points in Israel’s history, God found the worship of the Israelites detestable, because their indifference to the vulnerable and the stranger was making a mockery of the justice that God had asked them to uphold. Whenever injustice became widespread, the prophets would urge the people to repent and turn back to God before having to face the consequences for their apathy. Catholic social teaching serves this same prophetic function for modern Catholics, who cannot be reminded too often of our responsibility to care for the least of these (cf. Matt. 25).

A noticeable strength of Kammer’s work is how he skillfully weaves together biblical and theological insights with contemporary social analysis. Early in the book, for example, Kammer reaches back to the Old Testament concept of the anawim, or “little ones,” which is a term that encompassed widows, orphans, strangers, and the poor. Kammer then shows how Jesus carried on this tradition of special care for the anawim—as for instance, with the Sermon on the Mount, in which he proclaimed divine blessedness for the poor, those who mourn, and the meek. Relatedly, when Jesus preached about the last judgment, he taught that at the end of the age the inheritors of the kingdom of God will be those who fed the hungry, welcomed the stranger, and visited prisoners. Through preaching this message, Jesus handed on the vocation of Israel to the new ecclesia that he was founding. In Kammer’s words, “As the Hebrew kings were charged with responsibility for the anawim, now the same theme is repeated in the image of Christ the vindicator at the end of history” (p. 58). We are able to count ourselves as part of God’s kingdom insofar as we practice works of mercy on behalf of the least of these, even if it will take until the end of time to see clearly the dividing line that separates the sheep from the goats. This admonition, Kammer argues, is equally binding upon Catholics today, who have the fullness of revelation and walk in the light of scripture, tradition, and the living magisterium—all of which emphasize the divine mandate to care for the poor.

One controversial move on Kammer’s part is his decision at the start of chapter four to voice a brief protest against the Church’s practice of reserving priestly ordination to men. I worry that Catholics who could benefit from Kammer’s treatment of CST might dismiss the work as a whole because of his dissent in this one area. If pressed on the matter, Kammer would undoubtedly argue that he feels compelled to confront injustice anywhere, even—or, perhaps, especially—if he perceives it within the bounds of his own community. One wonders though if Kammer’s brief aside on this topic accomplishes much of anything besides turning some readers off to his message. He does not present a developed theological case for the stance that he takes, and he leaves it up to the reader to figure out how this stance relates to the larger theme of this chapter, which focuses centrally on “standing with the poor.” Some readers will almost certainly be left wondering, “If the Catholic Church has dropped the ball with this longstanding practice, can we trust it as a reliable authority on such matters as economic and environmental justice?” Not all readers will fall in this boat, of course, but on a prudential level, Kammer may have been better served to save this dissenting opinion for a separate monograph, so that he could explain in depth why he thinks the Church has erred in its theology of holy orders.

That matter aside, Catholics who give Doing Faith Justice a fair hearing will undoubtedly find themselves challenged by the overall content of Kammer’s study. Throughout the book, Kammer is unrelenting in pressing Catholics to take seriously this facet of their tradition, and he convincingly shows how the Church’s stance on social justice transcends facile categorizations of liberal and conservative, left and right. When it comes to recent papal teaching, for instance, Pope Francis has followed the path marked out by Benedict XVI and John Paul II, and the substance of his witness hits the same emphases that characterized the magisterium of his immediate predecessors. To prove the point, consider the following statement (quoted on p. 319): “The needs of the poor take priority over the desires of the rich; the rights of workers over the maximization of profits; the preservation of the environment over uncontrolled industrial expansion; production to meet social needs over production for military purposes.” This quote is taken from an address by John Paul II, but one could just as easily expect to find it in the writings of Pope Francis, of Benedict XVI, or of Leo XIII, for that matter. As members of the body of Christ, we should be careful not to dismiss the Church’s prophetic teachings on matters of social import because they don’t readily fit into categories that we have inherited from mainstream political discourse. Our primary allegiance is to the kingdom of God; we should be able to demonstrate this allegiance by how we live our lives, both individually and as a corporate body. Kammer’s book fleshes out what this witness should look like in today’s world and, in that respect, rewards careful study of its contents.