The miracle of Aaron’s rod, which flowered overnight and bore ripe almonds, offers an antidote to the murderous retribution on those who had rebelled against the priestly authority of Aaron and his sons, described in the preceding chapters. With each rebellion, Moses determined to let the will of God prevail. And yet, when great numbers of rebels met with their death it only served to stimulate further dissent as Moses and Aaron were personally blamed for killing the Lord’s people.

Against this backdrop of punitive fire, plague, and burial alive, the miraculous blossom of Aaron’s rod reveals a life-giving and benevolent divine force. And yet, it is the rod which incites the people’s terror, who at last acknowledge that unrestricted access to the tabernacle of the Lord has fatal consequences and accept the elevated status of the Levites as ministers of the sanctuary.

Even before Aaron’s staff is placed inside the tent of the testimony, we have encountered it several times already (though whether the rod that blooms is the very same one described in earlier passages is a debate for another day). During the liberation of the Israelites from Egypt, Aaron’s rod is the channel for God’s power: turning the water of the Nile to blood (Exodus 7:19–20), summoning plagues of frogs and gnats (8:16–17), or transforming into a snake and devouring all the other staffs-turned-serpents which belong to the Pharaoh’s sorcerers (7:8–12). In contrast, in Numbers 17, this instrument of miracles becomes the object of one—and, crucially, in Aaron’s absence, thereby calls attention to the fact that Aaron has not chosen his role, but has been summoned to it by God. The rod is not wholly subject to Aaron’s individual will. The Hebrew word matteh which describes the tribal rods means ‘staff’ but also ‘tribe’ and ‘branch [of a vine]’. This wordplay is used carefully to foreground the genealogical inevitability of the Levites’ collective claim on the priesthood. They are a chosen people, existing apart from the other tribes as mediators between the people and an all-powerful God.

The earliest Christian commentators interpreted Aaron’s rod as a prefiguration of the resurrected Christ, who blossomed to life following his death on the wooden cross. The rod was also understood to bear witness to the budding stump of Jesse (cf. Isaiah 11), itself a prophecy of the coming of the Messiah.

In the Christian visual tradition, the iconography of Aaron’s rod is most commonly employed to foreshadow the Virgin birth and is often grouped together with other Old Testament episodes which were deemed similarly prophetic since they all feature the motif of a thing that remained untouched: Moses and the burning bush (which burned but was not consumed; Exodus 3), Gideon’s fleece (dry despite the dew all around it; Judges 6:36–40), and the closed gate of Jerusalem (which remained shut after the Lord had passed through it; Ezekiel 44:2). Such imagery proliferated especially in German territories during the fourteenth and fifteenth centuries (e.g. a diptych in Museo Nacional Thyssen-Bornemisza; Inv. no. 272 (1929.18.1), and an embroidered hanging in the Met Cloisters; Inv. no. 69.106).

The Vyšehrad Codex was probably given to King Vratislav II of Bohemia on the occasion of, or shortly after, his coronation of 1085. The depiction of Aaron’s rod early in the manuscript is explained by its twofold significance—as a reminder that the priestly elite are divinely elected, and as prefiguring the ‘fruit’ of the Virgin birth, Christ. The emphasis on a preordained genealogy offers a legitimizing context for the reign of the newly crowned monarch, who like Aaron was divinely elected. It is also a visual precursor to the subsequent pages of the manuscript which consists chiefly of extracts from the Gospels, with twenty-nine illuminated scenes from the life of Christ.

A similar inference regarding the continuity from Old to New Testament underlies the imagery of the Cologne altarpiece, though here the genealogical aspect seems less important and the rod’s prophetic implications in relation to the Virgin’s womb are underscored. This is unsurprising given the altarpiece’s provenance from a church dedicated to the Virgin.

Finally, the carved relief in Merseburg Cathedral, though certainly included in the cycle for its prophetic connotations, stands out from other traditional Christian depictions of Aaron for the special attention to his status as High Priest, a fitting emphasis given the priestly occupants of the choir stalls below.