The 1958 edition of Moral Theology by John A. McHugh and Charles J. Callan, revised by Edward P. Farrell, presents itself as a complete course grounded in St. Thomas Aquinas and supplemented by modern authorities. The preface explicitly aims to avoid digressions into canon law, dogmatic theology, or history, focusing instead on moral questions. Yet the excerpts reveal a persistent tension: the work constantly negotiates between abstract principles and concrete legal rules, between the theologian’s reasoning and the canonist’s code.

Systematic Order and the Avoidance of Digression

The preface announces a deliberate narrowing of scope: the authors intend to treat moral theology as a systematic whole, avoiding “alien fields” such as canon law or dogmatic theology. This is a response to the proliferation of specialized commentaries after the 1917 Code of Canon Law. However, the excerpts show that the line is difficult to maintain. In the discussion of restitution (sections 1788–1791), the text moves fluidly between moral principles (e.g., the order of preference among creditors based on justice) and civil law provisions (e.g., American bankruptcy rules). The authors do not simply cite the civil law; they integrate it as a practical norm, noting that “the order of preference among creditors according to civil law is generally as follows.” This suggests that the work’s systematic ambition is constantly checked by the need to address real-world legal frameworks.

Casuistic Detail and the Priority of Principles

The excerpts on restitution illustrate a hallmark of the casuistic method: exhaustive enumeration of cases. Section 1790 lists multiple scenarios for the “amount” of restitution when an object changes value during possession in bad faith, distinguishing internal vs. external causes and improvements vs. deteriorations. The text weighs competing opinions—e.g., whether uncertain debts need be paid only “in proportion to their probability.” This approach reflects the authors’ stated goal of not sacrificing “essentials for accidentals,” yet the sheer volume of distinctions risks overwhelming the reader. The underlying principle (the duty to restore what is unjustly taken) is clear, but the application requires navigating a thicket of hypotheticals. The work thus embodies a tension between the simplicity of moral law and the complexity of human transactions.

The Role of Authority and the Weight of Opinions

The text frequently invokes authority: St. Thomas Aquinas is the foundation, but the authors also cite “the best modern authorities” and refer to “common opinion” or “some” versus “others.” In the discussion of creditor priority, the work presents multiple views without always settling the matter: “Creditors who are certain are by some preferred to creditors who are uncertain; but others think that payment to the poor… is the latter’s presumed will.” This openness to divergent opinions is characteristic of moral theology as a discipline that reasons probabilistically. Yet the presence of the nihil obstat and imprimatur (from 1958) signals that the work operates within a defined doctrinal framework. The tension between authoritative teaching and scholastic debate is palpable: the text must guide consciences while acknowledging that reasonable theologians may disagree.

Readers approaching this work should expect a dense interplay of principle and case law. The authors’ effort to be comprehensive means that the text often reads like a legal manual as much as a theological treatise. Pay attention to how the authors balance the authority of Aquinas with the demands of modern civil codes and the diversity of theological opinions. The work rewards careful study but requires patience with its taxonomic structure.