For a brief summary of this and the preceding three chapters, see the earlier post: Aquinas On Degrees of Love For God.
The Perfection of Love of God That Falls Under Counsel
When St. Paul had said, "Not as though I had already attained, or were already perfect," and, "but I follow after, if I may by any means lay hold," he added shortly afterwards, "Let us therefore, as many as are perfect, be thus minded." From these words we can see that although the perfection of the blessed is not possible to us in this life, we ought, to strive to imitate it as far as we can. [The commandment of the love of God in one sense obliges us to love God in the manner possibly in this life, loving nothing else more than him, and at least implicitly directing to him everything we love and everything we do. But as St. Augustine points out, even the perfection of heaven is included in the commandment of love, not as though we are obliged to have this perfection here and now, which is not possible, but as a perfection for which we are to aim. And this commandment, obliging us to seek the perfection of love, is fulfilled the more perfectly, the more we employ helpful means to strive more for this perfection.] And it is in this that the perfection of this life consists to which we are invited by the counsels. [The counsels are such helpful means for growing in perfection.]
For it is manifest that the human heart is more intensely drawn to one thing, to the degree that it is drawn back from many things. Thus the more a man is freed from the affection for temporal things, the more perfectly his mind will be borne to loving God. Hence St. Augustine says that "the desire of temporal things is the poison of charity; the growth of charity is the diminishment of cupidity, and the perfection of charity is no cupidity." (Eighty-Three Questions, Book 83, Quest. 1). Therefore all the counsels, which invite us to perfection, aim at this, that man's mind be turned away from affection to temporal objects, so that his mind may tend more freely to God, by contemplating him, loving him, and fulfilling his will.
[Every created good is good by sharing in God's goodness. And nonetheless giving up created goods is helpful for growing in love of God. This is because of the limitation of human nature, which on the one hand, has a limited power of attention and of love, and on the other hand, cannot all of the time see things only in relation to God. "A person has only one will and if that is encumbered or occuped by anything, the person will not possess the freedom, solitude, and purity required for divine transformation" (St. John of the Cross, Ascent of Mount Carmel, book 1, ch. 11).
Indeed, when we desire things or persons in full subordination to God, e.g., when we love other persons as created in God's image, as loved by God, and as persons for whom we desire beatitude in God, then our love for these things or persons is not really a separate love from the love of God, and is no hindrance to the intensity of love for God. St. John of the Cross says, "[When one is not encumbered by attachments], a person remains unencumbered and free to love all rationally and spiritually, which is the way God wants them to be loved…. [This] love is according to God and exceedingly free. If the love contains some attachment there is greater attachment to God, for as the love of neighbor increases so does the love of God, and as the love of God increases so does the love of neighbor" (Ascent of Mount Carmel, book 3, ch. 23).
But in fact, in our imperfection and weakness, we do not, cannot always desire and love only in reference to God. And when a man considers and desires created goods without full reference to God (seeing them as participations in God, images of God, or ways to God), then his attention and love is divided, and he thus cannot give as intense love and attention to God. And this is the basic reason why, other things being equal, giving up temporal goods offers a person the possibility of a freedom of mind and heart which, if he puts to good use, will help him grow more surely in the love of God and neighbor.]
See also: Texts of Aquinas on the Counsels
Commandments and Counsels (previous blogpost)