The usual custom is to mark liturgically the death day of a saint or blessed person. In the Church, this day is called the »birthday for heaven.«
Peter Friedhofen died on 21 December 1860. At first, Pope John Paul II had set the feast of the newly beatified Peter Friedhofen on 21 December. While this day might serve perhaps for the home churches in the houses of the Brothers of Mercy, the day is already generally »occupied« by the Advent mass of 21 December. The nearer time of preparation before Christmas begins on 17 December and is especially marked each day through the antiphon to the Magnificat at vespers, which all begin with »O«—the »O« antiphons of the hymn »O Come, O Come Immanuel.«
The Congregation for Sacred Rite has approved the request of the Bishop of Trier and declared 23 June as the commemoration of the Blessed Peter Friedhofen.
Each year on the »Peter Friedhofen feast« is held in honor of the Blessed Peter and the founder of the order especially remembered.