"To defend the truth, to articulate it with humility and conviction, and to bear witness to it in life are therefore exacting and indispensable forms of charity."
Pope Benedict XVI--Caritas in Veritate (1)
There are two points I would make regarding this short quotation. First, "to bear witness to it in life." The individual is called not merely to know, defend, and speak the truth, but to live it--a call much more profound and difficult. And secondly, the triumvirate of activities comprises "exacting and indispensable forms of charity." Indispensable.