The oldest surviving picture of the virtues as a fighting force is the Psychomachia, a Latin allegorical poem written by Prudentius around the year 400, in which personified virtues meet personified vices in single combat inside the soul. It is the text that gave the Latin West its habit of imagining moral life as a battle with named opponents, and it is the reason the contrary virtues are usually drawn as armed women rather than as abstractions.
Humility's combat in that poem is the one everybody remembers, because it is won by not fighting. Pride rides in mounted and armoured, making a long speech about her own lineage, and is defeated when her horse stumbles into a pit that Deceit had dug for someone else. Humility, on foot and silent, has only to walk over and finish what Pride's own momentum began. Hope then lifts her up.
That structure is doctrine in narrative form, and the medieval preaching tradition used it exactly so. The point is not that humility is stronger than pride but that pride is self defeating, and that the humble party's task is to stay out of the way of the collapse.
Humility acquired no fixed attribute in later art, which is why the atlas draws no emblem for it. Painters gave her downcast eyes, a lamb, or a crown set on the ground at her feet, and none of the three became standard. Where the cardinal and theological virtues arrive in a Renaissance programme with recognisable objects in their hands, the remedial seven mostly arrive as figures who have to be labelled.