Anton Schneider was born in Tokmok, Kirghiz SSR in the Soviet Union. His parents were ethnic Germans from Odessa in Ukraine. After the Second World War they were sent by Stalin to a gulag in Krasnokamsk in the Ural Mountains. In Krasnokamsk, his family was closely involved with the underground church. His mother, Maria, was one of several women who helped shelter Bl. Oleksa Zaryckyj, a Ukrainian priest, who would later be imprisoned in a gulag near Karaganda by the Soviet regime for his ministry and martyred in 1963. The family traveled to the Kirghiz SSR after being released from the camps. Later, they left Central Asia for Estonia, where they lived in Tartu. In 1973, shortly after making his first Holy Communion in secret, he emigrated with his family for Rottweil in West Germany.
In 1982, Schneider joined the Canons Regular of the Holy Cross of Coimbra, a Catholic religious order, in Austria. He took the religious name of Athanasius upon joining the order. He was ordained a priest on 25 March 1990. Starting in 1999, he taught Patristics at Mary, Mother of the Church Seminary in Karaganda. On 2 June 2006 he was consecrated Bishop at the Altar of the Chair of Saint Peter in the Vatican by Angelo Cardinal Sodano. In 2011 he was transferred to the position of auxiliary bishop in the Archdiocese of Astana. He is the General Secretary of the Bishops' Conference of Kazakhstan.
Bishop Schneider defends the traditional form of receiving Holy Communion (kneeling, on the tongue) in Roman Catholic liturgy. This is the theme of his book Dominus est, published in Italian, and since translated into English, German, Estonian, Lithuanian, Polish, Hungarian and Chinese. The book contains a foreword written by Malcolm Cardinal Ranjith, then the Secretary of the Congregation for Divine Worship and the Discipline of the Sacraments, the current Archbishop of Colombo and Metropolitan head of the church in Sri Lanka.
Bishop Schneider encourages Catholics who truly believe they are receiving Christ in the Blessed Sacrament should kneel and receive Communion on their tongues: "The awareness of the greatness of the eucharistic mystery is demonstrated in a special way by the manner in which the body of the Lord is distributed and received".
English liturgical scholar and commentator Alcuin Reid wrote in a review of Dominus est in The Catholic Herald: "Bishop Athanasius Schneider, a patristic scholar, appointed a bishop by Pope Benedict in 2006, has raised his voice in prophetic call for the western Church to recall the importance, if not the necessity, of returning to the previous discipline of the reception of Holy Communion kneeling and on the tongue."
Currently in the Catholic Church in many dioceses with the consent of the Holy See, the practice of standing and receiving communion on the hand is permitted. However, many Traditionalist Catholics consider this an unacceptable break from the Traditions of the Roman Church, and call for the practice to be banned on these grounds, and because of its tendency to spread particles of the Eucharist that remained on the hands of one who received. All Eastern Catholic Churches receive communion on the tongue while standing.
At a theological conference in Rome in December 2010, Bishop Schneider proposed the need for "a new Syllabus" (recalling the 1864 Syllabus of Errors), in which papal teaching authority would correct erroneous interpretations of the documents of the Second Vatican Council.