As was customary according to Hebrew law, a priest circumcised Jesus on the eighth day after his birth. Within this cavernous temple interior, that priest pierces the infant's skin with his knife. Simon Bening implied the building's enormity in part by cutting off pillars and statues at the edge of the image, which forcefully suggests the continuation of the space beyond the confines of the miniature.
Medieval Christians viewed the circumcision as related to the final events of Christ's life, his Passion and death, because he shed his first blood then. They often discussed Christ's first suffering as a kind of foreshadowing of his final sacrifice on the cross.