Kirk was born in
Sheffield on 21 February 1886 and was the son of
Frank Herbert Kirk who, in turn, was the son of John Kirk (died 1875), a Methodist minister. He was educated at
Sheffield Royal Grammar School and
St John's College, Oxford, obtaining a double first in classics. He was accepted for graduate study at
Keble College, but moved to London instead to work with the
Student Christian Movement (SCM). The group was beginning a ministry to the large numbers of Indian students that were coming to England to study. During his time in
London he also opened a residential hall for students of
University College, London known as Ealing Hall, served as an assistant to the Department of Philosophy there and held a number of executive positions with SCM. He was also active with the university's
Officers Training Corps, and was commissioned in the
Territorial Force as a
second lieutenant on 22 July 1909. He began the process to become ordained as an
Anglican priest and was ordained a deacon on 21 December 1912 and moved to a church near Sheffield to begin a curacy, intending to go back to Keble College to finish his graduate study. When the
First World War broke out, however, that proved impossible. Instead, he spent the war with the
British Army as a chaplain in
France and
Flanders. On 16 October 1914, he was commissioned in the
Army Chaplains' Department as a
temporary Chaplain to the Forces 4th Class (equivalent in rank to
captain). He was promoted to temporary Chaplain to the Forces 3rd Class (equivalent to
major) on 19 February 1917 while he was senior chaplain to the forces of a
division. He reverted back to Chaplain to the Forces 4th Class on 17 October 1917, having been re-posted. He relinquished his commission on 1 September 1921 and was appointed an
honorary Chaplain to the Forces 3rd Class. Kirk was able to return to
Oxford in 1919, as a Prize Fellow at
Magdalen College and tutor at
Keble College. He began working on his first book of moral theology,
Some Principles of Moral Theology, published in 1920. He adopted the method of casuistry, where general ethical principles are applied to the practical situations in which moral decisions are made. He revived the study of Christian ethics using
casuistry, drawing on the work of Caroline divine
Jeremy Taylor (1613–1667). In 1922 he was appointed Fellow and Chaplain of Trinity College and awarded a Bachelor of Divinity degree followed by a Doctor of Divinity degree in 1926. In 1927 he was named Reader in Moral Theology and in 1933 was made the Regius Professor of Moral and Pastoral Theology. His scholarly reputation rests on the books of moral theology that he wrote during the 1920s and 1930s, especially
Conscience and Its Problems and
The Vision of God: The Christian Doctrine of the Summum Bonum. In many ways he revived the study of
moral theology in the Church of England and is considered one of the leading moral theologians of the 20th century. ==Bishop of Oxford==