The Priests can be created from the Church and are mainly used for healing other friendly units. However, priests are unable to convert enemy units as can be done in the game's prequels. All civilizations use priests except the Ottomans, and the Imam is similar to the Priest. Priests, Imams, and Missionaries are similar to the Surgeon in that they can heal units; however, they cannot build Field Hospitals. They also cannot heal ships. Unlike the first two Age of Empires, Priests take about 120 seconds to "recharge" after healing units.
"Religion was at the core of early colonial life, whether seeking religious freedoms in the New World or making the arduous journey to convert the Native Americans. Priests, pastors, and lay leaders of the various settlements, colonies, and missions sought to give strength to the struggling communities, binding them together through the bond of shared faith.
Though he was never ordained, William Ames’ works made him a prominent theologian in the New World, though he never made it to the colonies. Persecution for non-conformist religious practices sent him to Holland, where he spent many years teaching and writing, dogged by the British sovereignty until he decided that it was time to venture to the New World. He grew sick and died before he could make the trip, but his works were treasured by Protestant colonists in the New World."