Garrison is the senior pastor of Central Christian Church (Disciples of Christ) in Uniontown, Pennsylvania. He has also served as pastor of congregations in Alabama, Tennessee, Georgia, and Nova Scotia (Canada). He is a graduate of Alabama Christian College (B.A.), Southern Christian University (M.A. and M.Div.), and Columbia Theological Seminary (D.Min.). Additional graduate study has included independent preaching study with Fred Craddock. He has taught ministry and homiletics at Southern Christian University (Montgomery, Alabama) and Atlantic School of Theology (Halifax, Nova Scotia).