The ceremony in which the priest removes the Sacred Host from the tabernacle and places it on the altar for the adoration of the faithful. It may be public or private, differing only in rite. In public exposition the Sacred Host, having been removed from the tabernacle, is placed in a monstrance and elevated above the altar-table, usually in a niche above the tabernacle proper. In private exposition the priest merely opens the tabernacle and draws to its door the ciborium containing the Hosts for Holy Communion. For public exposition there is required some public cause. The days on which this exposition may take place are defined and outlined in the, Code of Canon Law and the pespective folios of faculties granted by bishops to their priests. For days other than those thus outlined a special permission of the Ordinary of the diocese is required. For the private exposition any good and reasonable cause is sufficient. The ceremony was properly introduced in the 14th century, under the influence of the newly established feast of Corpus Christi, and its frequency in the 15th century caused the development of the present code of rules.