 It is often assumed that the primary purpose of prophecy is to foretell the future, but this is not always the case. In the great monotheistic religious traditions (Judaism, Christianity, and Islam), for instance, a prophet is taken to be a person who makes God’s will particularly clear, whether or not this involves making predictions about the future. As William Hasker says, in these traditions, prophets are usually involved in “witnessing to the people concerning God’s purposes and requirements and seeking to recall them to obedience” (Hasker 1989, 194). There are fascinating debates in these religious traditions, especially in the medieval period, debates that we will not discuss here (see Kreisel 2001, Shatz 1998, Rahman 2011, Lorch 2016, López-Farjeat 2014, and the entries in this encyclopedia concerning the key figures discussed in those sources). Related questions about how a human person might come to know God’s will through some kind of revelation are also discussed elsewhere in this encyclopedia, for example in the entries on  the epistemology of religion  and  philosophy and Christian theology.