Saint Jacob of Nisibis, also known as Saint Jacob of Mygdonia, Saint Jacob the Great, and Saint James of Nisibis, was a hermit, a grazer and the Bishop of Nisibis until his death.

The grazers or boskoi are a category of hermits and anchorites, men and women, in Christianity, that developed in the first millennium of the Christian era, mainly in the Christian East, in Syria, Palestine, Pontus, Mesopotamia, and Egypt. However, the majority of them were situated in Palestine and Syria.