[1] After graduating from Regis High School in New York City in 1931, he studied at Georgetown University in Washington, D.C., earning a Bachelor of Arts degree in 1935.
[5] He received his episcopal consecration on November 30, 1964, from Cardinal Spellman, with Bishops Christopher Weldon and John Maguire serving as co-consecrators, at St. Patrick's Cathedral.
[5] He remained executive director of Catholic Charities until 1966, when he became episcopal vicar of Staten Island and pastor of St. Peter's Parish.
[4] Following the death of Archbishop Celestine Damiano, Guilfoyle was named the fourth bishop of the Diocese of Camden by Paul VI on January 2, 1968.
[6] During his tenure, Guilfoyle erected eight parishes, eleven convents, twenty-three churches, thirty-seven rectories, and six schools.
[6] Guilfoyle served for many years on the Administrative Board of the National Conference of Catholic Bishops, holding membership on a number of its committees, including those on priestly life and ministry, conciliation and arbitration (on which he also served as chairman), bishops, diocesan boundaries, budget and finance, Latin America, ecumenical, and motion pictures.