Origin
The origin of the pastoral staff is at times associated with the shepherd's crook. Whether the usage was borrowed from this source is doubtful. Some writers trace an affinity with the lituus, or rod used by the Roman augurs in their divinations, while others again ace in the crosier an adaptation of the ordinary walking-sticks which were used for support on journeys and in churches before the introduction of seats (Catalani, Pont. Rom., Proleg., xx). At all events, it came at a very early date to be one of the principal insignia of the episcopal office. Just how soon is not easily determined, since in the early pas- sages of the Fathers in which the word occurs it cannot be ascertained whether it is to be taken literally or metaphorically (see I Cor., iv, 21) or whether it designates an ecclesiastical ornament at all. In liturgical usage it probably goes back to the fifth century (Kirchenlex., s. v. Hirtenstab). Mention of it is made in a letter of Pope Celestine I(d. 432) to the Bishops of Vienne and Narbonne. Staffs have indeed been found in the catacombs that date from the fourth century but their ceremonial character has not been established. The first unequivocal reference to the crosier as a liturgical instrument occurs in the twenty-seventh canon of the Council of Toledo (633). At present it is employed by bishops whenever they perform solemn pontifical functions, by right in their own dioceses and by privilege outside, and by inferior prelates whenever they are privileged to exercise pontifical functions.