Fuller was lecturer in Biblical Studies at Allen Hall, St Edmund's College, Ware, Hertfordshire, from 1936 to 1949, for the Newman Association from 1950 to 1954, and at St Mary's College, Strawberry Hill, Twickenham, from 1968 to 1972. He then spent three years in Kenya as lecturer in Old Testament Studies at the University of Nairobi from 1972 to 1975. While there he availed himself of the opportunity to indulge some of his recreational interests and with members of the university staff went mountain climbing and visited Mount Kenya and the Ngorongoro Crater, and admired the wild-life in Serengeti/Tanzania and the Victoria Falls in Zimbabwe.