From The Bestiary of Christ by Louis Charbonneau-Lassay

The weasel is the smallest European carnivore; it is also the most graceful and one of the most intelligent. It accustoms itself quite easily to man, and develops a singular attachment to the person who takes care of it. Buffon and Mme. Delaistre confirm this, and Christian hagiography agrees with these authors, informing us that the Dominican saint Jordan of Battberg had as his familiar a weasel that was his regular companion; in pictures of him, one always sees the tiny animal at his side or in his hand.

Searching for symbolic images that would convey serious Christian lessons, the early glossarists pointed out that although the weasel is the smallest of the carnivores, yet it can win combats with much bigger animals than itself - so, they said, the weasel is the perfect symbol of a Christian who, no matter how weak in himself, can still triumph over Satan, the most terrifying monster of hell.

Writers of the last pre-Christian centuries imitated, apparently without understanding, an extremely ancient and enigmatic expression which seems to have been current in the whole of the ancient world: "The weasel conceives through the ear and gives birth through the mouth." Plutarch connected this assertion to humanity's earliest times and the very origin of the human language. Aristotle, Ovid, and other ancient naturalists recited the same dictum without understanding it all, it would see. This is yet another proof that in the last centuries before the birth of Christ the key had been lost to a host of symbols and enigmas relating to the most ancient metaphysical concepts and religious mysteries.

"The weasel conceives through the ear and gives birth through the mouth"; likewise, the disciple and also the initiate, listening to the word of the master, receives through the ear the seed of wisdom and of inner light which impregnates his spirit; then having thus learned much through attentive listening, the candidate for initiation becomes in his turn a teacher, and through the wise and eloquent speech of his mouth gives birth to disciples who are his spiritual children.

The idea of choosing the weasel as the symbol of the perfect disciple is certainly unexpected, and seems incongruous; however, it is understandable if one takes into account that "damoiselle weasel, of long and fluid body" was formerly, in some countries, one of the emblems of flexibility, and that flexibility of mind is the first quality necessary for a disciple to become a perfect disciple. - Let whoever wishes search and find if he can a better resolution to the ancient enigma, that the weal "conceives through the ear and gives birth through the mouth"; I wil adhere to the one I have proposed until there is a better explanation from someone more qualified than myself.

Although the Ancients classified the weasel as an inauspicious animal that one would be better off not to meet on one's path, they did recognize its extreme familial tenderness and care in constantly moving its young so that enemies could not find them, or so that they would be better sheltered. This habitual movement from one place to another explains why certain symbolists made the weasel their allegorical image of inconstancy, but others, looking further and higher, saw in it a symbol of carefulness, vigilance, and active paternal affection. Given the old symbolists' way of thinking, it did not take much to place the weasel among the fauna symbolic of Jesus Christ: this occurred at the moment when one of them, Brunetto Latini, took upon himself to write: "The weasel often transports its young from place to place so that no one will find them, and if she finds them dead, many people say that she resuscitates them, but how she does this they do not know." So in its own way, the weasel shares the symbolism of revivification with the lion and the pelican.

The Ancients were not unaware of the weasel's services in destroying rats, mice, field mice, shrews, and other little ravagers. Phaedrus demonstrates this for us in his fables. Pliny adds that the two European species of weasel wage a vicious war on snakes, and that their spleen is an effective remedy for the bites of venemous animals. I have heard the peasants who live in the swampy countryside around Poitiers say that vipers never remain where weasels have made their holes. Pliny also tells us in two other passages of his great work that the weasel is the most implacable vanquisher of that terrifying reptile, the basilisk or cockatrice: "This monster," he says, "as has often been proved for kings withing to see its corpse, cannot withstand weasels, which lure it into a cave and kill it by the odor they exhale." In another passage he says that the weasel itself will pursue the cockatrice into its lair, where everything nearby is burned by the reptile's breath. Then, with nothing but its odor, the weasel kills it, and dies at the same time. All the ancient Christian symbolists note of this duel in which the little animal triumphs over the most dangerous of monsters, and kills it by means of its own death. In the works of medieval writers and artists, the weasel became the image of the Savior.

In Christian symbolism, rats and mice which spoil everything are among the emblems of the vices which corrupt the soul. So the weasel, which hunts and destroys rats and mice, was also adopted as the symbol of the one who purifies the world by hunting down the vices that destroy whatever is good. The weasel also sometimes symbolized a means of purification; this is without doubt based on the old legend that said that this animal's scent is enough to purify its dwellings from the presence of filthy reptiles, and also that with this alone it slays the infernal cockatrice.

This idea is in accord with the old peasant superstition that regarded wearing a weasel skin as an effective preventative of poisoning from harmful vapors and infectious diseases. Pliny also says that the weasel's spleen is a very good remedy for snake venom. According to Aristotle, weasels are careful to feed on rue before fighting with snakes, because the reptiles detest the odor of this plant. Rue was one of the plants of the ancient pharmacopoeia used to cure people in the early stages of leprosy, also mange and scurf; but all such skin diseases were constantly taken in the symbolism of Christian spirituality as symbols of sin. The idea of purification emerges from all these diverse elements.

A slightly larger variety of the weasel is the ermine, which changes color with the seasons: in summer it wears a tawny coat with light grey underneath; in winter, it is entirely clothed in snow-white, except for the tip of its tail, which is black. This complete winter white belongs only to norther weasels; in France the animal is greyish and not very handsome.

Popular imagination of the past pictured the ermine as an amphibious animal which only visited clear streams, meadows, or mossy, flowering woodlands, and which hated dirt to the point that it would let itself be killed rather than tread on muddy ground and soil its immaculate coat. Seizing on this fiction, medieval heraldry took the ermine as the symbolic image of a man determined to protect the purity of his conscience - an image that is, above all, that of the perfect knight who prefers to undergo any misfortune rather than tarnish his name and his escutcheon by the slightest act contrary to loyalty, fidelity, or knightly honor. It is in this sense particularly that many old and noble families, first and foremost aof which were the ancient sovereign dukes of Brittany, adopted or received the ermine as the insignia on their coats of arms. The Breton dukes displayed it everywhere in their castles and cities with the proud motto: Potius more quam foedari: "Better die than defile myself."

Thus placed as the perfect sign of the soul's purity, the ermine shares the symbol of the crucifixion with the swan, the dove, the lily, and the snow, embodying the innocence of Christ. Also, the ermine was one of the rare winter symbols of the Resurrection, because, while brown in summer, it then seemed to disappear, only to reappear in all its whiteness with the return of the snowy season.