Dr. Keen was born for the first time in Newton, West Virginia, on December 1, 1939. He was born again in Akron, Ohio, on the second Sunday of October 1958, at the Akron Baptist Temple under the ministry of Dr. Dallas Billington. He was first introduced to the church through the bus ministry as an eight-year-old boy. As young adults, Mary and he were saved they moved to Pontiac, Michigan, to enroll in Midwestern Baptist College and joined Emmanuel Baptist Church where Dr. Tom Malone was both president and pastor.

At MBC Keen completed his course work and graduated Magna Cum Laude. Upon graduation in 1964, they moved to Milford, Ohio, where he spent thirty-five years as pastor of the First Baptist Church. The ministry, by the grace of God, was very fruitful and the church grew significantly.

In 1973 God used Dr. Don Frazier to put in the hearts of three men, Dris Caudill, Demarest, and Keen to start the Bearing Precious Seed (BPS) ministry. In 1999 God began to move in Keen's heart to start First Bible International (FBI) and he resigned as the pastor of First Baptist Church. First Bible International was born with the express purpose of getting the Bible to the billions of Bible-less people in the unreached people groups of the world. The work would be primarily in the 10/40 Window.

Keen serves on the adjunct faculty at The Crown College in Powell, Tennessee. The College conferred on him a Doctor of Divinity degree in 2010. The Keens have been married 56 years and have four children; all of them love God and serve the Lord. They also have sixteen grandchildren and fifteen great-grandchildren.

Dr. Keen has authored three books, Thinking Outside The Box, He Is Worthy and They Are Still Waiting and founding editor of the Unpublished Word Journal, the official publication of First Bible International, and numerous published