Numbers — Chapter 3

The Levites are applied to Aaron and the priests for service in the Tabernacle; Lapide notes that the Levites are like soldiers who stand guard between God and the people, mediating by their sacred ministry.

The names of the Levite clans contain moral teaching: Gershon = \"stranger\" (Ecclesiastics must live as pilgrims on earth); Caath = \"sorrowful\" (clerics must mourn the sins of the people); Merari = \"bitterness\" (they must meditate on death and novissima); Levi = \"brightness of purity.\"

God takes the Levites in place of the firstborn of Israel; all firstborn belong to God from the night of the Exodus, and the Levites serve as their substitutes in perpetual sacred ministry.