Marvin was ordained in 1957 as a minister in the Christian Church (Disciples of Christ) and served congregations in Oklahoma, Oregon, and Washington State. He retired as minister of the First Christian Church in Kent in 2000 after serving 33 years. He has degrees from Northwest Christian University and the Graduate Seminary of Phillips University. He served on the board of trustees of Northwest Christian University for 32 years and was awarded a doctor of divinity degree by the University. He has also served as a member for eight years and chair for one year of the Human Services Commission of the City of Kent; as a member for 11 years and one year as president of the board of directors of the King County Sexual Assault Resource Center; as a member of the General Board of the Christian Church (Disciples of Christ); and as a member and one year as chair of the board of Church Extension of the Christian Church. Marvin was a founding board member of the Kent Food Bank and Community Service Center and of the Kent Youth and Family Services.