The phrase highlights the resilience of a pure heart against negativity or harsh words. Regardless of how intense or powerful the curse might be, it is ultimately ineffective when faced with genuine goodness and integrity. This suggests that true strength lies not in the ability to withstand malice, but in the purity of one's character that allows them to rise above petty insults and negativity.

In the context of "The Last Unicorn," this idea reinforces the theme of innocence and the protection it affords individuals against the darkness of the world. A pure heart remains untouched and unscathed, demonstrating that kindness and goodness retain their power, making them formidable in the face of hostility.