Complex sentence: Because the Duration is, in fact, ineffable, the way toward understanding it can only be shown indirectly through images which can never show a complete picture of the Duration, for it can only ever be grasped through a simple intuition of the imagination.
Split into simpler sentences: Because the Duration is, in fact, ineffable, the way toward understanding it can only be shown indirectly through images. These can never reveal a complete picture of the Duration, for it can only ever be grasped through a simple intuition of the imagination.