Charles Cowan spent thirteen years as a Member of Parliament and for over thirty years he was a longstanding and founding member and advocate of the Sustention Fund Committee of the newly formed Free Church of Scotland. Within fifty years the fledgling denomination, in addition to paying the salaries of all its clergy through its Sustentation Fund, had built 730 new churches, 400 manses, 500 schools and a new theological college. Cowan, who was deeply committed to the principles of the new Free Church, took practical steps along with others to ensure that the rhetoric of the pulpit was supported by the generosity of the pew. Cowan was a wealthy man, intellectually curious with a reverence for learning. He joined the British Society for the Advancement of Science, was a member of the Royal Society of Arts and the National Association for the Promotion of Social Sciences. He was also a sponsor of the Moody-Sankey revival meetings. The House of Commons was not really his metier: he felt more at home at the family's paper mills in Penicuik, in the counting house, on the curling rink or with his large family.