On 13 April 2015, Dew was appointed a member of the Congregation for the Evangelization of Peoples and of the Pontifical Council for Promoting Christian Unity. He participated in the Fourteenth Ordinary General Assembly of the Synod of Bishops (4–25 October 2015) on "The vocation and mission of the family in the Church and in the contemporary world". On 28 October 2016, was appointed a member of the Congregation for Divine Worship and the Discipline of the Sacraments.