From the tribute by Rev. Alan D. Falconer, WCC director of Faith & Order:
Having studied philosophy and theology in Canada, and undertaken postgraduate research at the University of St Thomas (the Angelicum) in Rome and at the Saulchoir, the House of Studies of the Dominican province of France, Fr Jean was ordained priest there in 1955 and in 1957 became professor of dogmatic theology at the Dominican College of Philosophy and Theology in Ottawa, and also taught at St. Paul University and at Laval University in Québec. An engaging and lively teacher, Fr Jean has influenced generations of theologians of the Roman Catholic Church and of other churches through his lectures at Oxford, Salamanca, Barcelona and Fribourg.
At Vatican II, Fr Jean was a “peritus” for the Canadian bishops. Subsequently Fr Jean became a consultant to the Pontifical Council for Promoting Christian Unity, and was involved in most of the important ecumenical developments in his church. Although he has written on a wide range of topics, his most important writing was in the field of ecclesiology with major studies on “The Bishop of Rome” and “The Church as Communion”. He became a deeply committed ecumenist, especially through his experience in the Anglican-Roman Catholic International Commission (ARCIC). His circle of friends expanded to embrace theologians from different traditions through his work with ARCIC (1968-2000), the Disciples of Christ (1977-2000) and the Orthodox-Roman Catholic Commission (1980-2000). A member of the Faith and Order Commission from 1975 and vice-moderator from 1977 until his death, he participated in a wide range of studies and was a major influence in the drafting of the convergence texts “Confessing the One Faith. An Ecumenical Explication of the Apostolic Faith” and “The Nature and Purpose of the Church”.