He served as director and professor at the diocesan seminary of Cascavel (1977–1978), the diocesan seminary of Toledo (1979–1982, 1993), and the Centro Interdiocesano de Teologia de Cascavel (1991–1993).
Before doing pastoral work in Toledo from 1985 to 1988, Scherer taught philosophy at the Ciências Humanas Arnaldo Busatto (1980–1985), and theology at the Instituto Teológico Paulo VI (1985). He then taught at the Universidade Estadual do Oeste do Paraná until 1994.
Pope Benedict XVI named Scherer as the seventh Archbishop of São Paulo on 21 March 2007. He replaced Cardinal Hummes, who was made Prefect of the Congregation for the Clergy. His appointment brought an end to almost four decades of Franciscan leadership of the archdiocese; before Hummes, Paulo Evaristo Arns led the diocese for 28 years. Scherer accompanied Pope Benedict for a great part of his visit to Brazil in May 2007, which was largely held in the former's see of São Paulo, and he delivered a speech during a ceremony to celebrate the Pope's arrival.
During the COVID-19 pandemic, Cardinal Scherer as Archbishop of São Paulo defended that churches remain open, but with a greater number of liturgical celebrations per day, in an attempt to prevent large gatherings.[10] Later, he declared the suspension of celebrations with the people.[11][12]
Views
General outlook
Scherer is considered to be theologically moderate.[13] He is one of just a handful of cardinals that use modern social media routinely.[citation needed]
Evangelization
According to a 23 July 2010, article by the website of the Catholic Zenit News Agency, Cardinal Scherer thinks there is an "evangelization deficit" around the globe today, which is why Pope Benedict established a new division of the Roman Curia to deal with that issue. Cardinal Scherer was quoted in the article as saying that the Pope "brings all to understand that this [new evangelization] is an objective of his, and that it must be the attitude of the Church worldwide, to respond to the challenges launched by the present 'change of age in the history of humanity.'"
Abortion
Cardinal Scherer asked Brazilians that if the country's Supreme Court legalizes abortion for fetus' with anencephaly, what will be the next group ‘incompatible with life’ to be eliminated?[14]
Liberation theology
He once criticized liberation theology's use of "Marxism as a tool of analysis," but supported its focus on social injustice and poverty (as fully in keeping with established, orthodox Catholic doctrine on these issues).[15][16]
Secularism in Brazil
Cardinal Scherer has argued that removing crucifixes in public places would not be in the best interests of Brazilian secularism.[17]
Priests and the liturgy
In reference to the popular Brazilian priest Marcelo Rossi, Scherer stated that, "Priests aren't showmen. ...The Mass is not to be transformed into a show".[18]