If you hold me up in a meadow so that the sun shines on my blade, the whole meadow will be lit up by my rays, and the horses in the field will approach of their own free will.

I can cut through brass, so you see, I am no ordinary knife. But I will only come into my power when I am in the hands of the one chosen by the princess to be king.

Enchanted Knife in The Enchanted Knife, Violet Fairy Book