The seed (Metaphor)
The cure names the bad people, such as the gypsies, Vianne, etc, “the seeds”, which spread everywhere and affect his obedience with discord. This metaphor is a kind of reference to the Biblical parable about the seeds. Some of the “good” seeds fell upon the ground where the “bad” seeds have already fallen. So, the “good” seeds are affected by those “bad” seeds. And the parable says that the second ones must be rooted in order not to compromise the first ones.
Eyes like the Earth (Metaphor)
Vianne says that her daughter has eyes which are “the blue-green of the Earth seen from a great height, shining”. Thus she shows how gently she loves Anouk, how valuable is the girl for her, and how deeply a mother can understand her daughter.
The cure is like a cat (Simile)
Vianne compares the cure with a cat: “…cold, light eyes which never hold the gaze, a restless watchfulness, studied, aloof.” Thus, she sees his inner essence: not very kind, sincere and good-natured.
Stranger (Metaphor)
Vianne often calls her daughter “my little stranger”. Thus she wants to show that she understands that it isn’t easy for her girl to wander around the world, to be a kind of ragamuffin. She wants her daughter to have better life, to have a home.