Quattuor abhinc annos
Quattuor abhinc annos (Latin for "four years ago") is the incipit of a letter that the Congregation for Divine Worship and the Discipline of the Sacraments sent on 3 October 1984 to presidents of episcopal conferences concerning celebration of Mass in the Tridentine form. == History == The letter explained that previously Pope John Paul II had invited comments from the bishops concerning the reception of the Missal promulgated in 1970 by authority of Pope Paul VI in accordance with the decisions of the Second Vatican Council, and any difficulties arising in the implementation of the liturgical reform.