Cowan studied philosophy at the undergraduate and postgraduate level at
Queen's University Belfast. He trained for ordination at
Oak Hill Theological College (MTh Distinction), and
Union Theological College (PG Cert Min), and subsequently completed doctoral studies at the
University of Cambridge with a dissertation entitled 'The prophetic preaching of
John Owen from 1646 to 1659 in its historical context'. Cowan served as assistant minister at First Presbyterian Church of
Saintfield and assistant to the vacancy convener in First Presbyterian Church of
Portadown. In 2016, he was ordained and appointed lecturer in historical theology at
Union Theological College. In 2018, Cowan was elected a Fellow of the
Royal Historical Society. Some of his work has been described as more theological than historical, and Cowan's work on the preaching of
John Owen is part of a new scholarly turn in Owen studies. Cowan has helped change Owen studies towards a more contextual interpretative approach. He has contributed towards the understanding of Owen as an exponent of prophetic preaching and has worked to raise the profile of John Owen studies, particularly in Northern Ireland. As a member of the Doctrine Committee of the
Presbyterian Church in Ireland and lecturer in historical theology at its seminary, Cowan addressed the decision made at the denomination's General Assembly in 2018 that it was necessary for people to make a "credible profession of faith" in order to receive the
sacraments, which precluded people in
same-sex relationships. == Publications ==