What St. Thomas teaches us about true law

A column by MATTHEW MCCUSKER

SCENE OF ST. THOMAS AQUINAS REFUTING THE HERETICS, FROM THE WAY OF SALVATION (1367). FRESCO BY ANDREA DI BONAIUTO. SANTA MARIA NOVELLA, FLORENCE.

In response to the Covid-19 outbreak governments worldwide have enforced draconian regulations, restricting some of the most fundamental liberties of free societies – the right of free association, the right to earn one’s daily bread by honest labour, and even the right to leave one’s own home. They have also used the crisis to further violate fundamental rights – such as violating the right-to-life by expanding provision of “home abortion”.

In the face of these violations of the most basic rights, there has been a high level of compliance, often on the grounds that “it is the law” and must be obeyed.

It will therefore be useful to consider the traditional teaching of the Church on the nature of law.

WHAT IS LAW? St. Thomas Aquinas teaches that the following is a complete definition of law:

Law is “an ordinance of reason for the common good, made by him who has care of the community, and promulgated”.1

Everything that conforms to this definition is a law. Nothing that fails to conform to this definition can ever be a true law, no matter what the purported lawgiver may claim.

We will examine each element of the above definition in more detail, but first we will briefly describe the four kinds of laws.

THE FOUR KINDS OF LAW St. Thomas teaches that there are four kinds of law.

1. The eternal law: by this law God governs “the whole community of the universe” by His “Divine Reason” and “Divine Providence”. St. Thomas teaches that “the very idea of the government of things in God the Ruler of the universe, has the nature of a law.”2 All creation is subject to the eternal law: “all things partake somewhat of the eternal law, in so far as, namely, from its being imprinted on them, they derive their respective inclinations to their proper acts and ends.”3

2. The natural law: the “participation of the eternal law in the rational creature is called the natural law.”4 By this law, imprinted on every human being, we are directed towards our proper natural ends: “the light of natural reason, whereby we discern what is good and what is evil, which is the function of the natural law, is nothing else than an imprint on us of the Divine light.”5

3. The human law: while the natural law directs us in “a general and indeterminate” way, it is often necessary for human happiness for legitimate authority to make “more particular determination of certain matters”.6 For example, while the natural law is sufficient for us to know that we shouldn’t kill others by poisoning, human law may give more precise regulations on how water companies use certain toxic chemicals. All human law is derived from the principles of the natural law.7

4. The divine law: this has been revealed by God to direct us to our supernatural end. St. Thomas gives four reasons why a divinely revealed law is necessary:

• the natural law directs us to natural happiness but not to supernatural happiness8 • our human judgement can suffer from “uncertainty… especially on contingent and particular matters… therefore, that man may know without any doubt what he ought to do and what he ought to avoid, it was necessary for man to be directed in his proper acts by a law given by God, for it is certain that such a law cannot err.”9 • human laws can only regulate external acts. Yet virtue requires also interior acts. Therefore, God

commands these internal acts through the divine law.10 • human law cannot punish all human acts, “since while aiming at doing away with all evils, it would do away with many good things, and would hinder the advance of the common good.”11 “In order, therefore, that no evil might remain unforbidden and unpunished, it was necessary for the Divine law to supervene, whereby all sins are forbidden.” 12

All four forms of law conform entirely to the definition of law given by St. Thomas, namely that law is “an ordinance of reason for the common good, made by him who has care of the community, and promulgated.”13

We will now examine each part of the definition in more detail, but with emphasis on its implications for laws promulgated by human beings. The eternal law, the natural law and the divine law are all promulgated by God Himself, for the common good, and in accordance with His Eternal Reason.14

A LAW IS AN ORDINANCE OF REASON “Law” states St. Thomas “is a rule and measure of acts, whereby man is induced to act or is restrained from acting”, consequently “it belongs to the law to command and to forbid.”15

All truly human acts must accord with reason.16 Therefore laws, which induce man to act or restrain him from acting, must also accord with reason.17

No command contrary to reason can have the nature of law:

“in order that the volition of what is commanded may have the nature of law, it needs to be in accord with some rule of reason.”17

Furthermore, as stated above, human law is derived from the natural law, “consequently every human law has just so much of the nature of law, as it is derived from the law of nature. But if in any point it deflects from the law of nature, it is no longer a law but a perversion of law.”19

A LAW IS ORDAINED TO THE COMMON GOOD Laws are always directed to the common good of the community for which they are ordained, whether that be the Church or the state. And the primary end of every law must be the end of human life itself, namely