Question — Merkelbach, Summa Theologiae Moralis
Question Three: On the Order of Charity
901. In charity order must be observed insofar as one thing ought to be loved more than another, according to comparison to the principle of the dilection of charity; which is twofold: the objective and final principle of beatitude and dilection, which is God, and the efficient principle of dilection, or the one loving himself. For the object of charity is the good loved, and this according to diverse grades insofar as one thing is better, or more proximate.
This order exists not only a) principally between diverse persons; but also secondarily, b) between diverse goods, some of which are more excellent or more necessary than others; indeed c) between diverse dilections or friendships, which, according to the diverse goods in which they are founded, are more excellent than others: for human goods, in which other conjunctions and friendships are founded, are ordered as to an ultimate end to the good upon which charity is founded, namely, to eternal beatitude; and therefore the conjunction and dilection of charity subordinates to itself all other honorable dilections, and commands the acts of every other honorable friendship (q. 26, a. 7).
"But he lives justly and holily who is an uncorrupted judge of things: and he is one who has ordered dilection, lest he either love what is not to be loved, or not love what is to be loved, or love more what is to be loved less, or love equally what is to be loved either less or more, or love less or more what is to be loved equally. Every sinner insofar as he is a sinner is not to be loved; and every man, insofar as he is man, is to be loved on account of God, but God on account of himself. And if God is to be loved more than every man, each one ought to love God more than himself. Likewise another man is to be loved more than our body: because all these things are to be loved on account of God, and another man can enjoy God with us, which the body cannot; because the body lives through the soul by which we enjoy God. But all are to be loved equally; but since you cannot profit all, one must chiefly consult those who, by opportunities of places and times or of any things whatever, are more closely joined to you by a certain lot."
Therefore between persons there is a threefold order: 1. between God and us, 2. between us and neighbor, 3. between various neighbors.