Rev. Provost did his undergraduate studies at Carroll College in Helena and his theological studies at the Catholic University of Louvain in Belgium, earning an M.A. and S.T.B. He was ordained at the American College in June, 1963. In 1967 he received a doctorate in canon law from the Lateran University in Rome.
From 1967 to 1979, Rev. Provost served as Chancellor and Officialis of the tribunal for the Diocese of Helena. He served as a member of the Canon Law Society of America, in 1977-1978 and as its Executive Coordinator from 1980 to 1986. The Society awarded him its highest honor, the Role of Law Award, in 1991.
In 1979, he joined the faculty of canon law at The Catholic University of America and served as Chair of the Department from 1987-1998. From 1980 until his death, he served as the managing editor of the faculty's journal, The Jurist.
Rev. Provost published scholarly, pastoral and popular articles in a variety of publications, including national and international canon law journals. He also lectured frequently on canonical and pastoral topics in the United States, Canada, Europe and Australia. He was a member of the board of directors of the Consociation Internationalis Studio Iuris Canonici Promovendo. For 10 years, he served as one of the directors for the Church Order section of the international theological journal Concilium. Since 1997, he had been a member of the Anglican-Roman Catholic Consultation in the United States.