ROCKFORD, Ill. (CNS) — A funeral Mass was to be celebrated Sept. 9 at the Cathedral of St. Peter in Rockford for retired Bishop Thomas G. Doran of Rockford, 80, who died Sept. 1 at his residence at Presence Cor Mariae in Rockford.

He had served as bishop from 1994 until his retirement from active ministry in 2012.

Bishop Doran had lung cancer surgery in December 2006 at the Mayo Clinic in Rochester, Minnesota. The upper fourth of his left lung was removed. He had to forgo Christmas celebrations in the diocese that year.

Two months before the surgery, he told about 30 Catholic newspaper editors in a homily, “You are responsible for the truth and bringing it to the people,” adding, “Never take for granted what your readers don’t know. Do not be afraid to teach and reteach them in the pages of your publications, and do it often.”

Born Feb. 20, 1936, he was ordained for the diocese in 1961. After a series of pastoral assignments, he served as secretary to the bishop from 1965 to 1968, was chancellor from 1969 through 1984 and served as episcopal vicar for education from 1982 to 1986. He also was cathedral rector from 1984 to 1986.

Bishop Doran had been auditor of the tribunal of the Roman Rota, the church’s central appellate court, from 1986 to his appointment to Rockford in 1994. In the early 1990s he was also a consultant to the Vatican Congregation for Clergy and a member of a special commission of the Congregation for Divine Worship and the Sacraments, dealing with cases of priests and deacons seeking dispensations from clerical celibacy.

His first pastoral letter, issued in 1998, cast its eye to the year 2000, when Bishop Doran told Catholic faithful of the diocese to “prepare for the great jubilee by a renewal of our eucharistic spirit.”

In 1999, Bishop Doran began a string of one-minute appearance on Rockford’s NBC affiliate that aired just prior to the “Today” show. “Top o’ the Morning With Bishop Doran” provided a brief commentary on the Gospel reading for the day. He also presented an eight-part series on the Catechism of the Catholic Church for the station. In 1998, he launched a weekly 25-minute program, “The Catholic Forum with Bishop Thomas G. Doran,” on a Rockford radio station. In addition, he appeared on a 13-part Eternal Word Television Network series on his book, “At the Crossroads: A Vision of Hope.”

For the U.S. Conference of Catholic Bishops, he served in the early 2000s as chairman of its Committee on Canonical Affairs. In 2001, he had been appointed to the Vatican Congregation for Clergy, giving him particular expertise when he became one of five U.S. bishops on a joint commission with Vatican officials to review and revise special norms adopted in 2002 for dealing with priestly sex abusers, and then to determine how they had worked. He also served on the bishops’ Ad Hoc Committee on Sexual Abuse.

Bishop Doran served on a second ad hoc committee in 1998 to study a 1997 Vatican instruction on lay ministry, “Instruction on Certain Questions Regarding the Collaboration of Nonordained Faithful in the Sacred Ministry of the Priest.” He had an additional assignment that year, serving on the bishops’ Committee on Women in Society and in the Church. In 1997 he served on a subcommittee to prepare a second draft of proposed norms to implement St. John Paul II’s 1990 apostolic constitution on higher education, “Ex Corde Ecclesiae.”

Bishop Doran also served a dozen years as president of the Institute for Religious Life, which seeks to foster growth, development and renewal of consecrated life, especially among vowed religious.

In a 2007 statement, Bishop Doran and the other Illinois bishops said the vitality and economic success of the United States come, to a great extent, as a result of immigration. While the homelands of people who wish to come to the U.S. also have a responsibility to improve life for them, they added, “as immigrants do continue to come here, we also know that their vitality, work and presence have made and will continue to make our nation even greater.”

In 2003, Bishop Doran and the Illinois bishops called the “Left Behind” book series contradictory to Catholic teaching. “These materials are, in fact, a marketing tool for fundamentalist preaching about the end times and a thinly disguised polemic against the Catholic Church,” they said.