Listers, the following is SPL’s presentation of the Angelic Doctor’s treatment of war as taught within his Summa Theologica II-II.40. All four articles have been address and summarized and can be seen in full list form by clicking the title-links. The “Just War Theory” is arguably one of the most misunderstood and misrepresented doctrines within the Church and within society as a whole. Along with Aquinas’ treatment, SPL has included a bonus list laying out the current Catechism of the Catholic Church’s teachings on war and peace.



“I drew an assault boat to cross in - just my luck. We all tried to crawl under each other because the lead was flying around like hail.” Crossing the Rhine under enemy fire at St. Goar. - Wikipedia, Common Domain

#1 Catholics and War: 7 Thoughts from St. Thomas Aquinas

Listers, the following section is taken in its entirety from St. Thomas Aquinas’ Summa Theologica: II-II.40.1. The Angelic Doctor discusses War under those things contrary to Peace, which is itself listed under the “Mother of All Virtues,” Charity. For the sake of clarity – especially for those not familiar with the structure of the Summa Theologica – SPL has taken the liberty of including headings and rearranging the question – body, then the questions with their corresponding answer (St. Thomas poses questions/statements contrary to the truth and the responds). As the reader will note, St. Thomas’ theory of a “just war” – which is primarily pulled from St. Augustine – differs considerably from what modernity has touted as the “Just War Theory.”

Teachings 1. The Authority Whose Care Is the Common Weal 2. A Just War 3. Peace, Punishment, & the Good

Questions 4. Are Not All Wars Sinful? 5. Does Not Scripture Advocate Pacifism? 6. Since War Is Contrary to Peace, Is It Not a Sin? 7. If Wargames Are a Sin, Is Not War?


April 19th, 2003: 7th Marine Regiment Chaplin, Father Bill Devine, Boston, Massachusetts speaks to Marines from 5th Marine Regiment during Catholic Mass at one of Saddam Hussein’s palaces in Tikrit, Iraq in support of Operation Iraqi Freedom. 1st Light Armored Reconnaissance Batalion is part of the 1st Marine Division from Camp Pendleton, California. Operation Iraqi Freedom is the multinational coalition effort to liberate the Iraqi people, elliminate Iraq’s weapons of mass destruction and end the regime of Saddam Hussein. (Official USMC photograph by LCpl Andrew P. Roufs) (RELEASED)

#2 Clerics and War: 6 Thoughts On Whether It Is Lawful for a Priest to Fight

Listers, in the Angelic Doctor’s Summa Theologica, he addresses the question of whether or not it is lawful for a priest or bishop to wage war. St. Thomas Aquinas takes up his question on war under vices contrary to peace which is a species of the mother of all virtues, charity. The question on priests and war is his second article under the question of war, which follows the first article discussing St. Augustine’s Just War theory. ST II.II.40.2

Teachings 1. Incompatible Duties 2. Ministry of the Altar

Questions 3. May Clerics Fight in Defense of the Vulnerable? 4. Can Clerics Take Part in Wars in Any Fashion? 5. Is It a Sin for Clerics to Go to War? 6. Why Should Clerics Abstain from Just Wars?


#3 Tactics: 6 Thoughts on Whether It Is Lawful to Lay Ambushes in War

Listers, in his third article discussing war, St. Thomas Aquinas raises a question of “just tactics” or rather whether or not ambushes and other “deceptive” maneuvers are permissible in a just war. The Angelic Doctor speaks of war under the heading of those things which are contrary to peace, and peace is listed as a species of charity, the mother of all virtues. ST II.II.40.3

Questions 1. If it is deceptive, is it not unjust? 2. If it is a form of lying, is it not unjust? 3. If we love our enemies, how can we deceive?

Teachings 4. On the Authority of Scripture 5. Rights and Covenants of War 6. The Lawful Art of Concealment


Heads bowed, members of 1RAR attend a mass conducted at Coral by Father George Widdison, a Roman Catholic Padre, for those who died during the fighting at the base in May and June 1968. [AWM THU/68/0595/VN

#4 Holy War: 6 Thoughts On Whether One Can Fight On A Holy Day

Listers, St. Thomas Aquinas ends his four article question on war by asking whether or not is it lawful to fight on holy days? He addresses war as a something contrary to peace, and peace is listed as a species of charity, the mother of all virtues. ST II.II.40.4

Arguments Against Fighting on Holy Days 1. Acts of War Violate the Sabbath Rest 2. Acts of War Are Greater than Other Violations 3. Possible Temporal Harm Is Not an Excuse

Aquinas’ Argument For Why It Is Permissible 4. The Jews Lawfully Warred On Holy Days 5. Christ Showed Acts of Safety Are Lawful 6. Safeguarding the Common Weal


Holy Michael the Archangel, defend us.


“Thou Shall Not Kill” and War: 16 Teachings of the Catholic Church

Listers, the following is the Catechism of the Catholic Church’s treatment on war, which is discussed under the 5th Commandment – “Thou Shall Not Kill.”

Peace 1. Mortal Sin & Praiseworthy Anger 2. Levels of Hatred Toward Thy Neighbor 3. Peace Is Not Merely the “Absence of War” 4. He Who Killed Hostility 5. Those Who Renounce Violence

Avoiding War 6. The Intentional Destruction of Life 7. Cannot Be Denied Lawful Self-Defense 8. The Just War Doctrine 9. Servants of the Security and Freedom of Nations 10. Conscientious Objectors and Service 11. War Does Not Suspend the Moral Law 12. Resist Immoral Orders 13. Modern Crimes Against God and Man 14. Moral Reservations of the Arms Race 15. Gun Control 16. Beat Their Swords into Plowshares