Christians affirm the value of human life and seek peace. More than that, Christians are called to love their neighbour as themselves and therefore, to understand that the life of their enemy is as valuable in God’s sight as is their own. Violence against others is an issue on which there is a different emphasis in the Old and New Testament. The Old Testament treats war and violence as normal and legitimate.

“Accursed is the one who is slack in doing the work of the Lord; and accursed is the one who keeps the sword from bloodshed” Jeremiah 48.10.

By contrast Jesus’ words and actions in the New Testament offer a model of non-violence.

“But I say to you that listen, ‘Love your enemies, do good to those who hate you, bless those who curse you, pray for those that abuse you’.” Luke 7. 27-29

The Christian Church has adopted different views on war and violence in different circumstances. The early Church although persecuted, took Jesus’ model of non-violence as its guide. During the time when Christianity was the majority religion of the Roman empire, the Church had to consider the practical and political issues on which governments must take positions. On the issue of the state’s recourse to warfare, the view came to prevail that the state could, according to specific criteria, enter into and conduct war justly.[1] This theory drew on pre- Christian classical philosophy, for example Homer’s Iliad shows that warfare has been infused with some moral concepts namely that of honour, although such “lofty” concerns are not obvious in Thucydides’ History of the Peloponnesian War which stresses state interest rather than moral behaviour.[2]

The idea of the circumstances in which a war could be justifiable was put forward by St Augustine of Hippo in the fourth century and later elaborated by St Thomas Aquinas in the 13th Century in his Summa Theologicae as well as by Hugo Grotius[3] in the 17th Century and has given rise to the “Just War” theory. Other attempts at limiting certain kinds of warfare include international agreements such as the Geneva and Hague Conventions.[4] In 1928, a pact signed by all nations of the League of Nations even made war illegal[5]. As far as the Church of England is concerned attitudes to war are “not defining matters for Anglican orthodoxy”[6] and various valid views are held. “Many members of the Church believe that pacifism is the Christian way most true to New Testament witness.”[7] However, Article 37 of the 39 Articles of Religion states that, “It is lawful for Christian men, at the commandment of the magistrate, to bear weapons and serve in the wars.”[8]

In the just war theory, criteria are set out for the legitimate resort to war in the “Jus ad Bellum”, the principles of how the war should be carried out in the “Jus in Bello” and in what kind of relations should apply in the aftermath of war or “Jus post Bellum”.

According to the “Just War” theory, a war can only be considered morally just if the country using military force can demonstrate that there is a just cause. The clearest example of a just cause is self-defence against an aggressor which may include the invasion by another country but what about a pre-emptive strike as in the case of the Six Day War of 1967?[9]. Other examples of a moral defence of war include assisting an invaded friendly nation, human rights violations. Indeed, the US Catholic Conference defined a just cause as “force may be used only to correct a grave public evil, i.e. aggression or massive violation of the basic rights of whole populations”[10]. Of course, the problem here is that not all potential enemies are as obviously evil as the Hitler regime in World War 2. [11]

Basically, there are another five conditions which must be satisfied for a war to be considered just: the war must be declared by a lawful authority, the intention behind the war must be good, all other ways of resolving the problem should have been tried first[12], there must be a reasonable chance of success, and the means used must be in proportion to the end that the war seeks to achieve.[13]

The “Just War” theory also includes the way a war is fought, or Jus in Bello. There should be a distinction between soldiers and civilians. This however, is fraught with difficulties as in modern warfare a civilian worker is also helping the economy of the country.[14] What about soldiers dressed as civilians, for example the Vietcong in the Vietnam war? Yet, the enemy cannot be grouped into one targetable mass of people, i.e. soldiers. The second principle is that any offensive action should be strictly proportional to the object desired. At the battle of Omdurman in 1898 In the Sudan six machine gunners killed thousands of dervishes. Perhaps the gunners were right in the sense they were defending themselves., but the principle of proportionality means that this is a massacre.[15] Jus in Bello also requires that the agents of war be held responsible for their actions. The issues that arise from this “include the morality of obeying orders (for example when one knows those orders to be immoral) as well as the moral status of ignorance (not knowing the effects of one’s actions)”[16]

There is less agreement on the rules of jus post bellum. However, it is possible to apply a number of the values expressed in jus ad bellum and jus in bello to form an outline.[17] Firstly, the rights whose violation justified the war should be secured. Secondly, just as the declaration of war must be publicly made by the proper authority, so must the declaration of peace. Thirdly, proportionality governs both jus ad bellum and jus in bello, and so it should govern the peace settlement as well. It should be reasonable, not a form of revenge, which will likely fuel resentment and further aggression[18]. Fourthly the discrimination between combatants (including political leaders) and non-combatants still applies when seeking punishment. Public, international trials for war crimes should be conducted. A fifth set of considerations relates to the rehabilitation of the aggressor state. Does justice require or permit the state to be disarmed? Does it allow for training in respect for human rights, or even political institutional reform to secure this?

In the twentieth century and later, the concept of any form of “just war” has to be modified in the light of the development of nuclear armament and weapons of mass destruction as well as the “war on terrorism” invoked by George W Bush.[19]

Therefore, there are certain circumstances when a war could be deemed to be “just” but even when the cause of the war can be justified, as in the start of the second world war, it does not mean that certain aspects of the way it is carried out can also be called “ethical”.[20] Wars are violent, brutal, bringing death and destruction, hardly in keeping with the concept of “loving your enemy”. They are so often the result of human weakness, the desire for greed or fear of the “other”. As Carl von Clausewitz, the great philosopher on war, wrote in the nineteenth century “All war presupposes human weakness and seeks to exploit it. ”[21] Clausewitz did not necessarily write from a Christian viewpoint but perhaps he does reflect the idea that wars occur because we are living in what Christians would call “a fallen world” and if conflict and aggression are part of the human condition, it should be agreed that some wars can be considered just in certain circumstances. √√

(1245 words, excluding quotations)


Book of Common Prayer 1563

Church of England Ethical Investment Advisory Group, Defence Investments Policy May 2010

Carl von Clausewitz: On War

David Fisher: Morality and War 2011

Michael Lacewing:

Alexander Mosely: Article in Internet Encyclopedia of Philosophy at

Michael Walzer: Just and Unjust Wars 1977


Internet sources:

US Catholic Conference 1993 quoted in–Briand Pact

[1] Church of England Ethical Investment Advisory Group, Defence Investments Policy May 2010

[2] Just War Theory from Internet Encyclopedia of Philosophy at

[3] De Jure Bellli ac Pacis 1625. Grotius was one of the first to define expressly the idea of one society of states, governed not by force or warfare but by actual laws and mutual agreement to enforce those laws. 

[4] Hague Conventions 1899 and 1907, based on the Lieber Code issued by Abraham Lincoln to Union forces in US and dated 1863 and Geneva Convention of 1949 which amongst other things banned the use of poison gas and land mines.

[5] Kellogg-Briand Pact

[6] Church of England Ethical Investment Advisory Group ibid

[7] ibid

[8] Thirty Nine Articles Book of Common Prayer 1563

[9] Israel was the first to use military force and appeared to be the aggressor. However, Egypt had already announced a policy of hostility towards Israel, put its military forces on maximum alert announced the closure of the Straits of Tiran to Israeli ships and formed mutual support treaties with Iraq, Syria and Jordan.

[10] US Catholic Conference 1993

[11] “We have discovered that there is something more horrible than war-the killing of the spirit in the body, the Nazi contempt for the individual man. The world reeks with the foulness of the crimes in occupied Europe, where a Dark Age has begun anew”. Times Literary Supplement 1941, quoted in

[12] Charter of UN 2.3 “all members shall settle their international disputes by peaceful means”

[13] Michael Lacewing at

[14] Notably in World Wars 1 and 2, when the failure of the German economy played an important part in its defeat.

[15] Another example is the Battle of Culloden in 1746 when the Duke of Cumberland ordered “No quarter” and the English soldiers went on to kill the wounded as well as supporting civilians.

[16] Quoted in “Just War theory” from Internet Encyclopedia of Philosophy at

[17] Michael Lacewing at

[18] A good example of this is the Treaty of Versailles 1919

[19]  metaphor of war referring to the international military campaign that was launched by the U.S. government after the September 11 attacks in the U.S. in 2001. Wikipedia

[20] Both the bombing of Dresden, not a highly obvious military or economic target in April 1945 and the use of atomic bombs on Nagasaki and Hiroshima, 6th and 9th August 1945

[21] Carl von Clausewitz “On War”