|Reference style||The Most Reverend|
|Spoken style||Your Excellency|
Steinbock was born in Los Angeles, California and was ordained to the priesthood by James Cardinal McIntyre on May 1, 1963. He then served as associate pastor in two parishes in East Los Angeles until 1972, whence he was appointed administrator of Santa Isabel Church on December 11, also in East Los Angeles. Steinbock later became associate pastor (April 1973) and parochial vicar (February 1, 1981) of St. Vibiana's Cathedral. He was President of the Los Angeles Priests' Council from 1979 to 1980, as well as a member of the Board of Consultors of the Archdiocese of Los Angeles from 1979–82.
On May 29, 1984, Steinbock was appointed Auxiliary Bishop of Orange and Titular Bishop of Midila by Pope John Paul II. He received his episcopal consecration on the following July 14 from Timothy Cardinal Manning, with Bishops William Johnson and Manuel Moreno serving as co-consecrators. Steinbock became vicar general of Orange on July 18, 1984, and diocesan administrator on July 29, 1986. He was later named the third Bishop of Santa Rosa on January 27, 1987, and the fourth Bishop of Fresno on October 15, 1991.
In 2003, Steinbock published a book of 100 vignettes from his 21 years ministering to the poor, immigrants and gang members in East Los Angeles and skid row. In this book "Ministry of Presence," he said that the ministry of a Catholic priest is primarily one of presence. He reportedly wrote: "One may not be able to respond to the many problems in people's lives, but one can be with them in their sufferings and joys. And the priest is with the people, so that they understand that the Lord Jesus is with them, loving them, suffering with them." His personal motto as bishop was "All for the love of God."
Bishop Steinbock died on December 5, 2010, in Fresno at age 73. He had been diagnosed with cancer in August and had been hospitalized at St. Agnes Medical Center in Fresno due to blood clots for about a month before his death. On Thursday, December 1, 2011, about a year later, Pope Benedict XVI appointed the Bishop of the Roman Catholic Diocese of El Paso, Bishop Armando Xavier Ochoa, as his successor, the fifth Bishop of the Diocese.
- Cheney, David M. "Bishop John Thomas Steinbock [Catholic-Hierarchy]". www.catholic-hierarchy.org.
- "Bishop Armando X. Ochoa, D.D." The Roman Catholic Diocese of Fresno.
- "Notice of Death of Roman Catholic Bishop John Steinbock," Diocese of Fresno Pastoral Center, December 5, 2010
- "Bishop Steinbock dies", The Madera Tribune, December 6, 2010, p. A1
- "Notice of Death of Roman Catholic Bishop John Steinbock". Diocese of Fresno Pastoral Center, December 5, 2010
|Catholic Church titles|
|Preceded by |
Mark Joseph Hurley
| Bishop of Santa Rosa |
George Patrick Ziemann
|Preceded by |
José de Jesús Madera Uribe, MSpS
| Bishop of Fresno |
Armando Xavier Ochoa