A missionary tells others about God and Jesus, and helps people. To become a missionary, one must take history and a foreign language in high school. In college, one needs to take foundational courses, MDIV courses in context, theology, interpretation, and mission over 6 years to earn a BA and Masters in Divinity. The cost per year at Abilene Christian University is $38,250, and income as a missionary would be $0 with donations from churches to support the work.