... 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. Charity, in fact, “rejoices in the truth” ...
... Truth needs to be sought, found and expressed within the “economy” of charity, but charity in its turn needs to be understood, confirmed and practised in the light of truth. In this way, not only do we do a service to charity enlightened by truth, but we also help give credibility to truth, demonstrating its persuasive and authenticating power in the practical setting of social living. This is a matter of no small account today, in a social and cultural context which relativizes truth, often paying little heed to it and showing increasing reluctance to acknowledge its existence ...
Through this close link with truth, charity can be recognized as an authentic expression of humanity and as an element of fundamental importance in human relations, including those of a public nature. Only in truth does charity shine forth, only in truth can charity be authentically lived. Truth is the light that gives meaning and value to charity. That light is both the light of reason and the light of faith, through which the intellect attains to the natural and supernatural truth of charity: it grasps its meaning as gift, acceptance, and communion. Without truth, charity degenerates into sentimentality. Love becomes an empty shell, to be filled in an arbitrary way. In a culture without truth, this is the fatal risk facing love. It falls prey to contingent subjective emotions and opinions, the word “love” is abused and distorted, to the point where it comes to mean the opposite. Truth frees charity from the constraints of an emotionalism that deprives it of relational and social content, and of a fideism that deprives it of human and universal breathing-space ...
... Truth, by enabling men and women to let go of their subjective opinions and impressions, allows them to move beyond cultural and historical limitations and to come together in the assessment of the value and substance of things ...
... Truth preserves and expresses charity's power to liberate in the ever-changing events of history. It is at the same time the truth of faith and of reason, both in the distinction and also in the convergence of those two cognitive fields. Development, social well-being, the search for a satisfactory solution to the grave socio-economic problems besetting humanity, all need this truth. What they need even more is that this truth should be loved and demonstrated. Without truth, without trust and love for what is true, there is no social conscience and responsibility, and social action ends up serving private interests and the logic of power, resulting in social fragmentation, especially in a globalized society at difficult times like the present ...
First of all, justice. Ubi societas, ibi ius: every society draws up its own system of justice. Charity goes beyond justice, because to love is to give, to offer what is “mine” to the other; but it never lacks justice, which prompts us to give the other what is “his”, what is due to him by reason of his being or his acting. I cannot “give” what is mine to the other, without first giving him what pertains to him in justice. If we love others with charity, then first of all we are just towards them. Not only is justice not extraneous to charity, not only is it not an alternative or parallel path to charity: justice is inseparable from charity<1>, and intrinsic to it. Justice is the primary way of charity ...
Another important consideration is the common good. To love someone is to desire that person's good and to take effective steps to secure it. Besides the good of the individual, there is a good that is linked to living in society: the common good. It is the good of “all of us”, made up of individuals, families and intermediate groups who together constitute society. It is a good that is sought not for its own sake, but for the people who belong to the social community and who can only really and effectively pursue their good within it. To desire the common good and strive towards it is a requirement of justice and charity. To take a stand for the common good is on the one hand to be solicitous for, and on the other hand to avail oneself of, that complex of institutions that give structure to the life of society, juridically, civilly, politically and culturally, making it the pólis, or “city”. The more we strive to secure a common good corresponding to the real needs of our neighbours, the more effectively we love them ...
http://www.vatican.va/holy_father/benedict_xvi/encyclicals/documents/hf_ben-xvi_enc_20090629_caritas-in-veritate_en.html