ASPERSION. — It is the act of sprinkling holy water upon persons or objects, usually by means of a metal implement or twigs of certain plants (v. ASPERSORIUM). Water has always been used for purification, hence its widespread employment in various religions (v. RITE). It is therefore no wonder that revealed religions also made use of this rite to signify the purification of the body.
Under the Mosaic Law, purification by water was performed in three ways: by washing, by aspersion, and by immersion. In the Book of Numbers (19), we find a curious aspersion with lustral water mixed with the ashes of a red heifer. During the Feast of Tabernacles, the instructions were more numerous. Christian religion inherited from the Hebrew the use of lustral water, and selected from the sacred books the prayers and chants that still accompany the rite of aspersion. This rite dates back to the remotest antiquity, and traces of it are found in the Acts of Peter, written about 200, and in the Acts of St. Thomas, written about 232. In the Sacramentary of Serapion, besides the blessing of baptismal water, there are various formulas for the blessing of oil, water, and bread. In the East, at least from the 3rd century, there was a liturgical use of holy water to obtain healing from diseases and protection against demonic temptations; in the West, however, we must go back to the mid-6th century to find certain evidence. St. Augustine, St. Gregory of Tours, and St. Caesarius of Arles are silent on this subject. It is mentioned in a letter of Pope Vigilius to Profuturus of Braga (538), in the lives of St. Aemilianus, St. Mabus, and St. Wilfrid, and in the Liber Pontificalis, where reference is made to the Western custom of mixing salt with water in the blessing. The use of sprinkling water on Sundays dates back to Incarnatus (9th century); and it passed from the Gallican rite to the Roman. As for Baptism by aspersion, V. BAPTISM.