It is the privilege of those who fear love to murder those who do not fear it!

Sarton frames “fear of love” as a defensive posture that can turn aggressive: those threatened by openness, intimacy, or emotional truth may try to destroy it in others. “Murder” works both literally and metaphorically—ranging from social punishment and character assassination to the psychic killing of another’s vitality—suggesting that repression often seeks to police or eradicate what it cannot tolerate. The line also implies a grim social dynamic: people who live without that fear (who love freely, honestly, or nonconformingly) become targets precisely because they embody an alternative. The exclamation gives the statement the force of an indictment rather than a detached observation.