Louis Bouyer

Louis Bouyer, Cong. Orat. (17 February 1913 – 22 October 2004) was a French Lutheran minister who was received into the Catholic Church in 1939. During his religious career he was an influential theological thinker, especially in the fields of history, liturgy and spirituality, and as "peritus" helped shape the vision of the Second Vatican Council.
Along with Joseph Cardinal Ratzinger, Hans Urs von Balthasar, and others, he was a co-founder of the international review "Communio". He was chosen by the pope to be part of a team to initiate the International Theological Commission in 1969.
Biography.
Born into a Protestant family in Paris, Louis Bouyer, after a receiving a degree from the Sorbonne, studied theology with the Protestant faculties of Paris and then Strasbourg. He was ordained a Lutheran minister in 1936 and served as vicar of the Lutheran parish of the Trinity in Paris until World War II. In 1939, the study of the christology and ecclesiology of St. Athanasius of Alexandria led Bouyer to the Catholic Church.
Received into the Catholic Church in the Abbey of Saint-Wandrille (Seine-Maritime) in 1944, he entered the congregation of the priests of the Oratory, and remained with them the rest of his life. He was a professor at the Catholic Institute of Paris until 1963 and then taught in England, Spain, and the United States. In 1969 he wrote the book "The Decomposition of Catholicism," which presented what he saw as important liturgical and dogmatic problems in the Church.
Twice appointed by the pope to the International Theological Commission, he was a consultant at the Second Vatican Council for the liturgy, the Congregation of Sacred Rites and Secretariat for Christian Unity, recording in his memoirs a general negative impression of the Council. In 1999 he received the Cardinal-Grente prize of the French Academy for all his work. He died 22 October 2004 in Paris, a victim of many years of Alzheimer's. He was buried in the cemetery of the Abbey of Saint-Wandrille.