He is known for championing the pre-Vatican II liturgical traditions (such as Tridentine Mass) and practices of the Church and for protesting certain current policies, including some associated with Pope Francis.

Schneider's mother Maria was one of several women to shelter the Blessed Oleksiy Zaryckyy, a Ukrainian priest later imprisoned at the infamous Karlag and in 1963 martyred by the Soviet regime for his ministry.

In 2014, he compared them to "members of the clergy and even bishops who put grains of incense in front of the statue of the emperor or of a pagan idol or who delivered the books of the Holy Scripture to be burned."

[11] Schneider supports the liturgical tradition of receiving Holy Communion on the tongue while kneeling, which he explains as a sign of love for the body and blood of Jesus.

The book contains a foreword written by Malcolm Ranjith, then the Secretary of the Congregation for Divine Worship, currently Archbishop of Colombo and Metropolitan head of the church in Sri Lanka.

[15] In the book, Schneider writes that receiving Holy Communion in this way had become standard practice in the church by the 5th century and that Pope Gregory I strongly chastised priests who refused to follow this tradition.

"[16] Schneider has upheld the traditional teaching of the Catholic Church that divorce and remarriage constitute the mortal sin of adultery, which condition renders one ineligible to receive Holy Communion.

"[10] In 2016, Pope Francis released the apostolic exhortation Amoris laetitia which seemed to allow divorced and civilly remarried persons to take the Eucharist under some circumstances, and this was put into practice by some bishops, arousing intense controversy.

"[17] On April 7, 2018, Schneider, along with conservative cardinals Raymond Leo Burke and Walter Brandmüller, participated in a conference rejecting the outline proposed by German bishops to allow divorced and civilly remarried Catholics to receive the Eucharist.

[18] On August 25, 2018, Archbishop Carlo Maria Viganò, former apostolic nuncio to the United States, released an 11-page letter describing a series of warnings to the Vatican regarding sexual misconduct by Theodore McCarrick, accusing Francis of failing to act on these reports and calling on him to resign.

He stated in 2018 that heavy Muslim immigration during the 2010s was orchestrated by "international powerful political organizations...to take away from Europe its Christian and its national identity.

Schneider has offered Divine Liturgy in the Byzantine Rite numerous times, praising it as "permeated with respect, with reverence, with a supernatural spirit and adoration.

[26][27][28] On June 10, 2019, Schneider, along with cardinals Burke and Jānis Pujats, as well as Kazakh archbishops Tomasz Peta of Astana and Jan Paweł Lenga, published a 40-point "Declaration of Truths" claiming to reaffirm traditional church teaching.

Burke and Schneider criticized the Synod document for its "implicit pantheism," support for married clergy, a greater role for women in the liturgy, and excessive openness to Amazonian pagan rituals and practices.

[33] The book has received particular attention for its treatment of current topics and concerns, including the clarification of certain ambiguous statements in the documents of the Second Vatican Council and the Catechism of the Catholic Church, for which it has been both praised[34] and criticized.