[2] His parents were Irish immigrants, and one of his sisters is a member of the Sisters Servants of the Immaculate Heart of Mary, Immaculata, PA.[3] He received his early education at the parochial school of Our Lady of Lourdes Church[4] in Overbrook, and attended St. Thomas More High School for Boys[5] in Philadelphia from 1961 to 1965.

[2] At St. Thomas, he was a member of the National Honor Society, a player on the varsity basketball team, and the class valedictorian.

[2] Following his graduation from St. Joseph's, he joined the faculty of West Catholic Boys High School, where he taught social studies.

[6] In addition to his teaching duties, he coached the junior varsity basketball team and served as the school's athletic director.

"[3] That year he entered St. Charles Borromeo Seminary in Overbrook, where he earned a Master of Divinity degree summa cum laude.

[3] In addition to his academic and pastoral duties, he served as chaplain to the Serra Club (1987–2001) and the Ancient Order of Hibernians (1986–95), spiritual director of St. Charles Borromeo Seminary, and director of the archdiocesan pilgrimages to the National Shrine of the Immaculate Conception in Washington, D.C.[11] On June 28, 2004, McFadden was appointed auxiliary bishop of the Archdiocese of Philadelphia and titular bishop of Horreomargum by Pope John Paul II.

[12] Later that year, McFadden expressed his opposition to the holding of a gay rights event at his alma mater of Saint Joseph's University, saying, "While the Church asks that we recognize the unique dignity of every human person, it does not mean supporting a lifestyle that is contrary to the natural law".