Peace testimony, or testimony against war, is a shorthand description of the action generally taken by members of the Religious Society of Friends (Quakers) for peace and against participation in war. Like other Quaker testimonies, it is not a "belief", but a description of committed actions, in this case to promote peace, and refrain from and actively oppose participation in war. Quakers' original refusal to bear arms has been broadened to embrace protests and demonstrations in opposition to government policies of war and confrontations with others who bear arms, whatever the reason, in the support of peace and active nonviolence. Because of this core testimony, the Religious Society of Friends is considered one of the traditional peace churches.
 General explanation
Friends' peace testimony is largely derived from beliefs arising from the teachings of Jesus to love one's enemies and Friends' belief in the inner light. Quakers believe that nonviolent confrontation of evil and peaceful reconciliation are always superior to violent measures. Peace testimony does not mean that Quakers engage only in passive resignation; in fact, they often practice passionate activism.
The Peace Testimony is probably the best known testimony of Friends. The belief that violence is wrong has persisted to this day, and many conscientious objectors, advocates of non-violence and anti-war activists are Friends. Because of their peace testimony, Friends are considered as one of the historic peace churches. In 1947 Friends as a worldwide religious group were awarded the Nobel Peace Prize, which was accepted by the American Friends Service Committee and the then London Yearly Meeting's Friends Service Committee, now called Britain Yearly Meeting Peace & Social Witness on behalf of all Friends. The Peace Testimony has not always been well received in the world; on many occasions Friends have been imprisoned for refusing to serve in military activities.
Some Friends today regard the Peace Testimony in even a broader sense, refusing to pay the portion of the income tax that goes to fund the military. Yearly Meetings in the United States, Britain and other parts of the world endorse and support these Friends' actions. Quaker Council for European Affairs campaigns in the European Parliament for the right of conscientious objectors in Europe not to be made to pay for the military. It should be stressed that these Friends are not trying to get out of paying taxes and they would willingly give the money to peaceful purposes. Some do pay the money into peace charities and still get goods seized by bailiffs or money taken from their bank account.
In America, others pay into an escrow account in the name of the Internal Revenue Service, which the IRS can only access if they give an assurance that the money will only be used for peaceful purposes. Some Yearly meetings in the US run escrow accounts for conscientious objectors, both within and outside the Society.
Many Friends engage in various non-governmental organizations such as Christian Peacemaker Teams serving in some of the most violent areas of the world. Quaker author Howard Brinton, for example, served in the American Friends Service Committee during World War I.
 Development of Quaker beliefs about peace
George Fox, perhaps the most influential early Quaker, made a declaration in 1651 that many see as the first declaration of Friends' beliefs on peace:
- I told [the Commonwealth Commissioners] I lived in the virtue of that life and power that took away the occasion of all wars and I knew from whence all wars did rise, from the lust, according to James's doctrine... I told them I was come into the covenant of peace which was before wars and strifes were. 
The best-known version of this belief  was stated in a declaration to King Charles II of England in 1660 by famous Quaker Margaret Fell, following George Fox's imprisonment after an armed revolt by religious radicals in London in January; its issuance at this particular time was as much to remove any suspicion that Friends might have been involved as a desire to make their position clear. This excerpt is commonly cited:
- All bloody principles and practices we do utterly deny, with all outward wars, and strife, and fightings with outward weapons, for any end, or under any pretence whatsoever, and this is our testimony to the whole world. That spirit of Christ by which we are guided is not changeable, so as once to command us from a thing as evil and again to move unto it; and we do certainly know, and so testify to the world, that the spirit of Christ, which leads us into all Truth, will never move us to fight and war against any man with outward weapons, neither for the kingdom of Christ, nor for the kingdoms of this world. 
Some Quakers initially opposed this statement because it did not deny use of the sword to the magistrate or ruler of the state. It also contained no prohibition against paying taxes for purposes of war, something that would trouble Friends to the present.
 Friends' testimony to peace
Quakers have engaged in peace testimony by protesting against wars, refusing to serve in armed forces if drafted, seeking conscientious objector status when available, and even to participating in acts of civil disobedience. Not all Quakers embrace this testimony as an absolute; for example, there were Friends that fought in World War I and World War II. Some others were firm Christian pacifists. During extreme circumstances it has been difficult for some Quakers to engage in and uphold this testimony, yet Friends have almost universally been committed to the ideal of peace, even those who have felt the need to compromise on their testimony. Apart from the specific question of war, other ways in which Friends have testified to peace have included vegetarianism and a commitment to restorative justice.
The Religious Society of Friends was awarded the Nobel Peace Prize in 1947. The Nobel Prize was awarded to Friends for Friends' work to relieve suffering and feed many millions of starving people during and after both world wars. The Nobel prize was accepted by the American Friends Service Committee, along with the UK's Friends Service Council on behalf of all Quakers.
The first paragraph of the Presentation Speech reads: "The Nobel Committee of the Norwegian Parliament has awarded this year's Peace Prize to the Quakers, represented by their two great relief organizations, the Friends Service Council in London and the American Friends Service Committee in Philadelphia."
- Quaker Faith & Practice. Yearly Meeting. 1999. pp. 1.02.31. ISBN 0-85245-306-X.
- Fox 1651
- from George Fox's Journal
- A declaration from the harmless and innocent people of God, called Quakers, London: 1660, as quoted in: Britain Yearly Meeting [Ed] Quaker Faith and Practice: the book of Christian discipline of the Yearly Meeting of the Religious Society of Friends in Britain London: 1994, 24:04. The extract quoted is considerably abridged from the original declaration - full text of the original declaration is available: A Declaration from the harmless and innocent people of God, called Quakers
- The Nobel Peace Prize 1947 - Presentation Speech
- A Declaration from the Harmless & Innocent People of God called Quakers (text of the Quaker 'peace testimony,' on the Friends' Journal web site)
- Pamphlet from Philadelphia Yearly Meeting, RSF, on the Peace Testimony
- Quaker women and the Peace Testimony
- Some Early Statements Concerning the Quaker Peace Testimony
- 'Think Peace' - a series of six articles from Quaker Peace & Social Witness of Britain Yearly Meeting