Charity
"If I . . . Have not charity," says the Apostle, "I am nothing." Whatever my privilege, service, or even virtue, "if I . . . Have not charity, I gain nothing." Charity is superior to all the virtues. It is the first of the theological virtues: "So faith, hope, charity abide, these three. But the greatest of these is charity."
Source: Catechism of the Catholic Church (Vatican.va)