Before the reform of the rite by Pope Pius XII, the blessing of the palms occurred inside the church within a liturgy that followed the general outline of a Mass, with Collect, Epistle and Gospel, as far as the Sanctus. The palms were then blessed with five prayers, and a procession went out of the church and on its return included a ceremony for the reopening of the doors, which had meanwhile been shut. After this the normal Mass was celebrated.
