Dennis was born and grew up in Pulaski, Tennessee where he met his wife Linda. They were married in 1971. They have one daughter, Mary McCormick, who with her husband Andrew and son Graham, are also members of Central. He has a bachelors degree in Bible from Lipscomb University and a masters degree in psychology from the University of Tennessee. He preached at rural congregations in Middle Tennessee from 1970 to 1985. He has served as a deacon at Harpeth Hills Church of Christ and taught classes at Hillsboro Church of Christ before moving to Johnson City and Central in 2008. He has worked in business and consulting in human resources and serves as a chaplain with the TBI. Dennis has served as an elder since 2009.