Objection 1. It would seem that beneficence is not an act of charity. For charity is chiefly directed to God. Now we cannot benefit God, according to Job 35:7: "What shalt thou give Him? or what shall He receive of thy hand?" Therefore beneficence is not an act of charity.
Objection 2. Further, beneficence consists chiefly in making gifts. But this belongs to liberality. Therefore beneficence is an act of liberality and not of charity.
Objection 3. Further, what a man gives, he gives either as being due, or as not due. But a benefit conferred as being due belongs to justice while a benefit conferred as not due, is gratuitous, and in this respect is an act of mercy. Therefore every benefit conferred is either an act of justice, or an act of mercy. Therefore it is not an act of charity.
On the contrary, Charity is a kind of friendship, as stated above (23, 1). Now the Philosopher reckons among the acts of friendship (Ethic. ix, 1) "doing good," i.e. being beneficent, "to one's friends." Therefore it is an act of charity to do good to others.
I answer that, Beneficence simply means doing good to someone. This good may be considered in two ways, first under the general aspect of good, and this belongs to beneficence in general, and is an act of friendship, and, consequently, of charity: because the act of love includes goodwill whereby a man wishes his friend well, as stated above (23, 1; 27, 2). Now the will carries into effect if possible, the things it wills, so that, consequently, the result of an act of love is that a man is beneficent to his friend. Therefore beneficence in its general acceptation is an act of friendship or charity.
But if the good which one man does another, be considered under some special aspect of good, then beneficence will assume a special character and will belong to some special virtue.
Reply to Objection 1. According to Dionysius (Div. Nom. iv), "love moves those, whom it unites, to a mutual relationship: it turns the inferior to the superior to be perfected thereby; it moves the superior to watch over the inferior:" and in this respect beneficence is an effect of love. Hence it is not for us to benefit God, but to honor Him by obeying Him, while it is for Him, out of His love, to bestow good things on us.
Reply to Objection 2. Two things must be observed in the bestowal of gifts. One is the thing given outwardly, while the other is the inward passion that a man has in the delight of riches. It belongs to liberality to moderate this inward passion so as to avoid excessive desire and love for riches; for this makes a man more ready to part with his wealth. Hence, if a man makes some great gift, while yet desiring to keep it for himself, his is not a liberal giving. On the other hand, as regards the outward gift, the act of beneficence belongs in general to friendship or charity. Hence it does not detract from a man's friendship, if, through love, he give his friend something he would like to I keep for himself; rather does this prove the perfection of his friendship.
Reply to Objection 3. Just as friendship or charity sees, in the benefit bestowed, the general aspect of good, so does justice see therein the aspect of debt, while pity considers the relieving of distress or defect.
Source: Summa Theologica (New Advent)