In The United Methodist Church, Holsinger rose to national prominence through his membership on the 1989-92 churchwide Committee to Study Homosexuality. He resigned from the committee shortly before the 1992 General Conference in Louisville, KY, because he said the committee's report was "skewed toward liberal interpretations" of homosexual orientation and behavior. At the time, Holsinger declined the committee's invitation to be included in a minority report on the subject.

Since that time, Holsinger has consistently supported forces in the denomination opposed to the acceptance of gay, lesbian, bisexual and transgender people. He has served previously on the board of the Indianapolis-based Confessing Movement within The United Methodist Church, a 15-year-old unofficial organization dedicated to "preserving the apostolic faith", according to a statement on its web site. Current Confessing Movement board members include Asbury Seminary chancellor Dr. Maxie Dunnam and layman David W. Stanley, also a director of the Institute on Religion and Democracy.

Holsinger was elected to the Judicial Council at the 2000 General Conference in Cleveland, OH. He was nominated from the floor along with Judicial Council members Mary A. Daffin, an attorney from Houston, TX, and Rev. Keith D. Boyette of Spotsylvania, VA, in one of the most successful political campaigns launched by the combined forces of the Confessing Movement and the Good News caucus.

During Holsinger's term on the Judicial Council, the church's "supreme court" has ruled consistently against acceptance of homosexual people. In 2005, the council upheld the defrocking of Rev. Beth Stroud, a lesbian, affirming the church's prohibition against ordaining GLBT people. Also that year, the Judicial Council set off a wave of debate in the church by siding with a Virginia pastor who refused membership to an openly gay man in Decision 1032. Several annual conferences this year have adopted resolutions challenging the views expressed in Decision 1032.