What but the holy Church is figured by the ark? To which four rings of gold in the four corners are ordered to be adjoined, because, in that it is thus extended towards the four quarters of the globe, it is declared undoubtedly to be equipped for journeying with the four books of the holy Gospel. And staves of shittim-wood are made, and are put through the same rings for carrying, because strong and persevering teachers, as incorruptible pieces of timber, are to be sought for, who by cleaving ever to instruction out of the sacred volumes may declare the unity of the holy Church, and, as it were, carry the ark by being let into its rings. For indeed to carry the ark by means of staves is through preaching to bring the holy Church before the rude minds of unbelievers by means of good teachers. And these are also ordered to be overlaid with gold, that, while they are resonant to others in discourse, they may also themselves glitter in the splendour of their lives. Of whom it is further fitly added, They shall always be in the rings, nor shall they ever be drawn out from them; because it is surely necessary that those who attend upon the office of preaching should not recede from the study of sacred lore. For to this end it is that the staves are ordered to be always in the rings, that, when occasion requires the ark to be carried, no tardiness in carrying may arise from the staves having to be put in; because, that is to say, when a pastor is enquired of by his subordinates on any spiritual matter, it is exceedingly ignominious, should he then go about to learn, when he ought to solve the question. But let the staves remain ever in the rings, that teachers, ever meditating in their own hearts the words of Sacred Writ, may lift without delay the ark of the covenant; as will be the case if they teach at once whatever is required.
Gregory the Great, “The Book of Pastoral Rule of Saint Gregory the Great, Roman Pontiff, to John, Bishop of the City of Ravenna,” in Leo the Great, Gregory the Great, ed. Philip Schaff and Henry Wace, trans. James Barmby, vol. 12b, A Select Library of the Nicene and Post-Nicene Fathers of the Christian Church, Second Series (New York: Christian Literature Company, 1895), 23–24.