[3] As a child, DiNardo would pretend to celebrate mass in vestments sewn by his mother and at an altar his father constructed.

[5][4] In 1969, DiNardo was accepted as a Basselin Scholar in philosophy at the Theological College at Catholic University of America in Washington, D.C.

[3] Upon his return to Pittsburgh in 1991, DiNardo was named assistant secretary for education for the diocese and concurrently served as co-pastor at Madonna del Castello Parish in Swissvale, Pennsylvania.

He received his episcopal consecration on October 7, 1997, from Soens with Bishops Donald Wuerl and Raymond Burke serving as co-consecrators, in the Church of the Nativity of Our Lord Jesus Christ.

[3] DiNardo adopted as his episcopal motto: Ave Crux Spes Unica, taken from the Latin hymn Vexilla Regis and meaning, "Hail, O Cross, Our Only Hope.

In November 2014, at the USCCB fall meeting, DiNardo was elected as a delegate to the 2015 Synod of Bishops on the Family, pending Vatican approval.

[11] DiNardo promised to release a list of archdiocesan priests with credible accusations of sexual abuse of minors in January 2019.

[12] On January 30, 2019, DiNardo released a list of names of 40 priests from the archdiocese with credible allegations of sexual misconduct over the previous 70 years.

DiNardo was criticized for allowing Keller to offer mass publicly at his parish the morning after the list was released.