Natural Law

God created a rational and orderly universe and allows humans, as rational creatures living in his universe, to participate in his eternal law by determining for themselves what they should or should not do.

Natural law is all of the moral laws that are known by all people even though they are not written down. They are known simply by relying on reason, experience, and basic sense of justice.

Not applying to animals, which do not have the rational ability to choose to do good and avoid evil, natural law only applies to the voluntary actions of people.

Natural law provides arguments for morality that appeal to any person’s sense of what is right and wrong, regardless of where or when they live, and even if they have no religious faith.

By using natural law as a basis for human law, humans order themselves and their communities leading to freedom and happiness. When civil laws or immoral acts violate natural moral law it leads to injustice.

A deep sense of the basic goods:

Bishop Robert Barron

Laws that exist naturally:

St. Agnes and St. Rose

All who sin outside the law will also perish without reference to it, and all who sin under the law will be judged in accordance with it. For it is not those who hear the law who are just in the sight of God; rather, those who observe the law will be justified. For when the Gentiles who do not have the law by nature observe the prescriptions of the law, they are a law for themselves even though they do not have the law. They show that the demands of the law are written in their hearts,* while their conscience also bears witness and their conflicting thoughts accuse or even defend them on the day when, according to my gospel, God will judge people’s hidden works through Christ Jesus.

Romans 2: 12-16

How human beings participate in God’s plan:

The Thomistic Institute

Setting the stage for nearly all Catholic reason:


In man’s free will, therefore, or in the moral necessity of our voluntary acts being in accordance with reason, lies the very root of the necessity of law. Nothing more foolish can be uttered or conceived than the notion that, because man is free by nature, he is therefore exempt from law. Were this the case, it would follow that to become free we must be deprived of reason; whereas the truth is that we are bound to submit to law precisely because we are free by our very nature. For, law is the guide of man’s actions; it turns him toward good by its rewards, and deters him from evil by its punishments.Foremost in this office comes the natural law, which is written and engraved in the mind of every man; and this is nothing but our reason, commanding us to do right and forbidding sin. Nevertheless, all prescriptions of human reason can have force of law only inasmuch as they are the voice and the interpreters of some higher power on which our reason and liberty necessarily depend.

Pope Leo XIII, Libertas Praestantissimum, 20 June 1888

Humans can choose to follow God’s natural law or not:

St Thomas Aquinas Church, Papine

Conversing with people who disagree:

Catholic News Service

The natural law, present in the heart of each man and established by reason, is universal in its precepts and its authority extends to all men. It expresses the dignity of the person and determines the basis for his fundamental rights and duties: For there is a true law: right reason. It is in conformity with nature, is diffused among all men, and is immutable and eternal; its orders summon to duty; its prohibitions turn away from offense . . . . To replace it with a contrary law is a sacrilege; failure to apply even one of its provisions is forbidden; no one can abrogate it entirely.

Catechism of the Catholic Church 1956

Laws for all human beings, in all cultures, at all times:

DSPT – Dominican School of Philosophy and Theology

Natural law influences the behavior of believers and non-believers:

Karlo Broussard

The Truth, Goodness, and Beauty of the Catholic Church

Encountering brides of Christ:

Pints with Aquinas

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