This project explores the similarities and differences among a wide variety of religious approaches on issues of war and peace, especially concenring the use of armed force. So far, studies include:
War & Peace in World Religions (Scriptural Justifications) gives an overview of the approaches in the major scriptures of seven world religions, resulting in a series of three Research Reports:
Part I: Abrahamic Religions (pdf) (Christianity, Judaism, and Islam)
Part II: Religions of Indic Origin (pdf) (Buddhism, Hinduism, Jainism, and Sikhism)
Hinduism's Rāmāyaṇa and Just War Criteria (html) (pdf) shows that the Just War criteria can be found in this ancient Indian scripture, though with a distinctly South Asian historical flavour. More generally see: some links to Hindu texts.
On Sikhism, a paper titled "The Sword and the Turban: The Use of Armed Force in Sikh Thought" (html or pdf) was published in 2011 in the Journal of Military Ethics. A companion piece has been developed on "Modern Sikh Warriors: Militants, Soldiers, Citizens" (scheduled for publication in the same journal). More generally see: some links to Sikh texts.
Other religions are also being studied, including Baha'ism and religions of Far Eastern origin (Chinese traditional).
A general comparison of the Eastern/Western approaches to peace is provided in Lotus on the Lake: Eastern Spirituality & World Peace (html) (pdf). Also available in Japanese translation (pdf).
For the ways in which U Thant, the Buddhist UN Secretary-General (1961–71), dealt with ethical dilemmas during his tenure at the helm of the United Nations, especially the robust use of force by UN troops in the Congo (1961-64), see U Thant: Buddhism in Action (html) (pdf).

Work is being done to look at the interpretations of religious scriptures, with various schools of thought being examined.

A bibliography on "World religions on war and peace" has being compiled (html) and is being continually expanded. 

This endeavour on religious studies runs in parallel with work on the ethical  justifications for war and peace, titled the Just War project.