In this class, we will learn about and discuss the highly praised work by John Kelsay, Arguing the Just War in Islam. After a brief overview of the origins of Islam, we will discuss the process of and sources of shari'a reasoning, which Kelsay presents as the way in which Muslims have historically discovered the proper path of submission to God's will. We then turn to the evolving thinking about war and peace in the tradition of shari'a reasoning, from early precedents, which often introduce ideas quite similar to Christian just war theory, to the competing visions of contemporary Muslim thinkers.