Forty Hours' Devotion

Forty Hours' Devotion, in Italian called Quarant'ore or written in one word Quarantore, is a Roman Catholic liturgical action in which continuous prayer is made for forty hours before the Blessed Sacrament in solemn exposition. It often occurs in a succession of churches, with one finishing prayers at the same time as the next takes it up.

A celebration of such a devotion is begun by a Solemn Mass or "Mass of Exposition", and ended by a "Mass of Reposition". The latter concludes with a procession and benediction. The Blessed Sacrament is reposed in the tabernacle for the daily Mass, and then returned for exposition after Mass.

It is assumed that the exposition and prayer should be kept up by night as well as by day, but permission is given to dispense with this requirement when enough watchers cannot be obtained. In such a case the interruption of the devotion by night does not forfeit the indulgences conceded by the Holy See to those who take part in it.