Bonaventure — on Rev 4:4 (Collations on the Hexaemeron, Collation 7)

“Furthermore, these twelve virtues, doubled in prosperity and adversity, are represented by the twenty-four hours, twelve in the night of adversity and twelve in the day of prosperity. Likewise, they are doubled in the active and the contemplative life: in that sense they are represented by the twenty-four elders who turned sometimes to action and at other times to contemplation, for they do what is sensible and mature. Once more, the twelve virtues are doubled through practical and speculative contemplation: and in this they are revealed by the twenty-four wings of the four animals, each one of which had six wings. And here ends the First Vision and the work of the First Day.”