Martin holds degrees in history from Oxford and theology from Cambridge. He has researched and written extensively on Methodist history and recent publications include Methodism in Victorian Oxford (2023), and Anglican-Methodist Ecumenism: The Search for Church Unity, 1920-2020 (2022, co-edited with Jane Platt).

He is a Fellow of the Royal Historical Society and of the Society of Antiquaries. He has been a British Methodist presbyter since 1992 and serves currently as Superintendent of the Barnet and Queensbury Circuit, in North London. In addition, he chairs the Faith and Order and Heritage Committees of the Methodist Church of Great Britain.