A native of Bushwick, Brooklyn, Di Gangi graduated from Brooklyn College in 1943 and earned a Bachelor of Theology from Philadelphia'sWestminster Theological Seminary in 1946 and joined the Presbyterian Church in Canada, following additional postgraduate courses at The Presbyterian College, Montreal. He served congregations in Montreal, preaching in both English and Italian from 1946–51, in Hamilton, Ontario from 1951–61, where St Enoch's Church grew to a membership of over 1,000. He served on the Committee of Evangelism and Social Action of the Presbyterian Church in Canada, and was part of the group that produced the Declaration of Faith Concerning Church and Nation deemed a subordinate standard of the church in 1954. He then returned to Philadelphia to serve at the historic Tenth Presbyterian Church in from 1961-67. He returned to pastoral duties at Knox Spadina in Toronto, Ontario, where he was an Elder before becoming Interim Minister in 1987; and Senior Pastor from 1989-1992. In 2000, he retired to Ottawa where his son-in-law is a pastor. He also taught at Tyndale University College and Seminary ; and was named Professor Emeritus in Pastoral Theology. He served as the Canadian and North American Director of a missionary agency called Interserve from 1967-1988. He was designated an "Evangelist-at-Large" within the Presbyterian Church in Canada during the 1970s and 1980s, and hosted a radio broadcast Amazing Grace, sponsored by Presbyterian Men, and broadcast on a few stations, and also participated on other radio ministries in both Canada and the United States. He was also active in the formation and early years of the Evangelical Fellowship of Canada and served for two years as that organization's President from 1969. He was also a popular preacher, who preached at many special services, including Anniversaries, conferences, and at Evangelistic Meetings particularly in Canada, the USA, and in Italy. He was also involved in the formulation of papers connected to the Lausanne Covenant. Di Gangi authored many books dealing with the Christian faith, including A Golden Treasury of Puritan Devotion: Selections from the Writings of Thirteen Puritan Divines, Twelve Prophetic Voices, The Book of Joel: A Study Manual, and The Spirit of Christ. A chapter in Tenth Presbyterian Church of Philadelphia: 175 Years of Thinking and Acting Biblically by Philip Ryken deals with Di Gangi's pastorate of that church, where he was preceded by Donald Grey Barnhouse and succeeded by James Montgomery Boice.
The happy people: discovering our Lord's secret of real happiness as revealed in His Beatitudes. Agincourt, Ontario: Bible & Medical Missionary Fellowship, c1976.
Reaching the unreached: a report on the Canadian Consultation on Evangelism. Agincourt, Ontario: BMMF International/Canada, 1983.
Life and immortality. Agincourt, Ontario: Bible & Medical Missionary Fellowship, 1975.
The sufferings and the glory: a devotional study of the 22nd Psalm. Agincourt, Ontario: Bible & Medical Missionary Fellowship, .
The meaning of Christian discipleship. Agincourt, Ontario: Bible & Medical Missionary Fellowship, 1975.
A living church: compared to what the Bible says about a living church, is yours alive or in need of revival? Agincourt, Ontario: Bible & Medical Missionary Fellowship, .
