Without doubt, Augustine believed that human equality demanded justice for all. Without doubt, Augustine believed that charity and aid are owed to the poor and destitute. But Augustine’s idea of justice makes a key distinction that is not made today.
Modern social justice requires some assumptions, as Dr. Fleischacker explains . Those assumptions are:
- All human beings are equally deserving of respect (Smith, Rousseau, and Kant)
- Respecting human beings means promoting their free agency (Kant)
- All humans have capacities for agency that justice demands be developed (Kant)
- Society shapes the degree to which they can develop these capacities, especially in allocating resources to them (Marx)
- Society is a cooperative effort that we can shape and reshape if we wish, and as we wish (Marx)
It is clear that Augustine would agree with premise 1. It is not so clear how many others he would agree to. And it is not clear that he would agree with the assumption behind premise 1; the conflation of political justice and theological justice.
Augustine’s Context and Human Equality
Augustine did not differ substantially from Cicero on this score, in fact, Cicero had a profound influence on him. Cicero understood that, “Whatever definition of a human being one adopts is equally valid for all humans” and that, “there is no dissimilarity within the species.”
Socrates, and so it would seem Plato, likely agreed. As Alisdair MacIntyre writes, “When Socrates acknowledged a justice whose scope extends beyond the frontier of the polis in a way that the written laws of the polis do not, it was to be unwritten laws made by God that he appealed.”
Classical antiquity is the intellectual context that Augustine inherited. It is no secret that he was profoundly influenced by Plato (and therefore Socrates) and Cicero.
So it is not surprising that Augustine said in a sermon, “How can you have the faith to ask your God for something if you don’t take any notice of your people?. . . I’m not asking what you are like in your clothes, but what you were like when you were born. You were both naked, both feeble, both beginning a miserable life, and so both crying.” 
Augustine’s Dualistic Justice
In De Civitate Dei, we read “the fact is, true justice has no existence save in that republic whose founder and ruler is Christ” (IV, 5).
Sergey Trostyanskiy notes that in De Civitate Dei, the word ‘iustitia’ references at least two diverging ideas.  These two ideas correspond to a tension scholars find within Augustine’s writings.
Indeed, Augustine believed that justice is giving what is owed to each person — however, he believed that such justice is not possible. This justice requires that “just men, rightly related to God by an interior order,” be present. Much like Plato, Augustine sees justice as a virtue, and specifically, the virtuousness of an ordered soul. But indwelling sin is always present, destroying this order.
As Trostyanskiy writes:
According to Augustine, we have at least two ways of apprehending justice: transcendent and immanent. These two concepts of justice are perhaps not incompatible, yet they certainly have different origins and contents, one being indebted to classical thought and the other arising from biblical – eschatological matrix.
One scholar Trotsyanskiy references helpfully describes imminent justice as legal justice and the transcendent justice as religious justice.
The Social Justice movement conflates the two.
Modern social justice teaches that one person’s need places a demand on another. There is danger in the idea that a person’s need creates an obligation in the other, without this distinction. The necessity of our salvation does not create for God an obligation to save, for example. Paul takes great pains to belabor this. These distinctions, however, were clearly in Augustine’s mind. This is made evident by how he treated poverty and the poor.
It is because of this two-fold distinction that Augustine can make the following statement which no modern social justice advocate can:
I have admonished the rich; now hear, ye poor. Ye rich, lay out your money; ye poor, refrain from plundering. Ye rich, distribute your means; ye poor, bridle your desires… Seek only for a sufficiency, seek for what is enough, and do not wish for more.
Hence why Augustine does not say that refusal to have mercy on the poor is theft, but like unto it. Referring to the hard-hearted rich man, the Bishop of Hippo says, “Failure to share his surplus with the needy is like to theft.” It is not theft because the property does not rightfully belong to the poor. Therefore, they cannot demand it, as social justice advocates assume.
Political justice can always be demanded. Theological justice, however, includes mercy and compassion, which though owed, cannot be demanded. They are owed in a different sense.
To the secular mind, premise one of Fleischacker’s outline above includes both political and theological justice and injustice. Secular elites deny any validity to the theological sphere. Therefore, the justice and piety which exists in that sphere becomes subsumed, by necessity, into the political sphere. Charity is owed; if charity is not given, an injustice does occur. But this injustice is a theological injustice, to be dealt with by the church and by God. Not by the state and the sword.
Secular elites hold to the secular concept of social justice. However, justice is not only a right ordering of the soul, but justice is only justice when it is rightly ordered in each sphere.
Citations and Footnotes
 Samuel Fleischacker, A Short History of Distributive Justice, pg 123
 David Johnston, A Brief History of Justice, p 94
 Alisdair McIntyre, Whose Justice? Which Rationality? page 146
 Teresa Delgado, Augustine and Social Justice, p 100
 Teresa Delgado, Augustine and Social Justice, p 44-45
 Ibid p 44-45
 Philip Schaff, A Select Library of the Nicene and Post-Nicene Fathers of the Christian Fathers, p 368.
For Further Discussion:
The Development of Social Justice
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