theologian(n = noun.person) theologiser, theologist, theologizer - someone who is learned in theology or who speculates about theology;

   A person well versed in theology; a professor of theology or divinity; a divine. [1913 Webster]

theologian, n. a person trained in theology.

Etymology:
ME f. OF theologien (as THEOLOGY)

N  theology (natural and revealed), theogony, theosophy, divinity, hagiology, hagiography, Caucasian mystery, monotheism, religion, religious persuasion, religious sect, religious denomination, creed, article of faith, declaration of faith, profession of faith, confession of faith, theologue, theologian, scholastic, divine, schoolman, canonist, theologist, the Fathers, theological, religious, denominational, sectarian.