A monastic artist is a craftsman. His art is for liturgical use. He filters his art through prayer.
He forgoes his psychological idiosyncracies. Instead, he ensures that his art coheres with the direct contemplation of divine grace.
To the degree that a monk is passionately attached to his idiosyncracies, the purity of his contemplation of divine grace is obscured.
However, the reverse is also true. For this reason, the best icons make us want to pray. We see divine grace in them directly being imaged-forth before us.
This image is concrete, and the experience is concrete. No abstract thought or reasoning is required.