The four doctors of the Western church are: Gregory, Ambrose, Augustine, and Jerome.
Jerome, in addition to being a scholar and translator of Greek and Hebrew, was a familiar figure in the Middle Ages. The faithful were made aware of many episodes in saints' lives by their depiction in various works of art. In Jerome's case, the most popular scenes were of him
- in the wilderness as a hermit
- in his study as a translator and
- on his deathbed hearing the trumpet of judgment day.
Guarding his study or resting near his feet is a tame or pet lion. Sometimes the lion is asleep but his eyes remain open. At least in medieval art, lions could sleep with their eyes open as in the Psalm:
". . . . he that keepeth Israel shall neither slumber nor sleep" (King James, Psalms, 121, 4). Asleep or awake, I am sure that the lion was most effective in ensuring quiet in the study.
Thus, the iconography for Saint Jerome includes a cardinal's hat and a lion.
Saint Jerome was posthumously elevated to the rank of ordinal to show his stature in the hierarchy of the church. The lion comes from a story.
One day a lion came limping to Saint Jerome holding out his paw. On examination, Saint Jerome discovered that the lion's paw had a thorn in it. Jerome removed the thorn, cleaned the wound, and bound up the paw. For this, the lion was very grateful to Jerome. As a result, he took up residence at the monastery and even did chores.
Allegorically, removing a thorn - which represents sin as in the crown of thorns - is baptism or banishing the beast in man.
Meanwhile, back at the monastery, the lion was assigned the task of guarding a donkey that carried firewood to the monastery from the forest where it was cut. One day the lion went to sleep and must have closed both eyes. Merchants in a passing caravan saw the donkey unattended and stole him to serve as their beast of burden.
The monks thought the lion had eaten the donkey and, as a result, told him that he had to assume the donkey's tasks. So the lion began to haul the firewood to the monastery. This seems to me quite bold on the monks' part since a lion that can devour a donkey should not scruple at eating a monk or two. One day while carrying firewood tied on his back, the lion saw the same caravan returning with the monastery's donkey still in tow. With roars and threatening gestures the lion herded the caravan to the monastery. His roaring alerted the monks who came out and recovered their donkey and I hope, apologized to the lion. One would assume the rejoicing over finding the lost animal was great, especially on the part of the lion.
Amy Welborn's website