To say that love is a feeling and the like is really an un-Christian conception. This is the esthetic definition of love and therefore fits the erotic and everything of that nature. But from the Christian point of view love is the work of love. Christ's love was not intense feeling, a full heart, etc.; it was rather the work of love, which is his life. - Soren Kierkegaard, Journal X.1 A 489 (1849)
If you make use of your reason, you are like one who eats substantial food; but if you are moved by the satisfaction of your will, you are like one who eats insipid fruit. - St. John of the Cross, Sayings of Light and Love, 46.
The view that feelings, emotions and desires are irrelevant to the moral life has fallen on hard times. Defenders of Kant go out of their way to argue that Kant held no such view (and are probably right to do so), as if holding such a view were a terrible disqualification. The idea that on some moral view it is better to visit a friend out of a consciousness of duty than out of friendly feeling is taken as a reductio of that view. Typical utilitarians ground the moral life in feelings, emotions and desires (happiness is taken to be pleasure or the satisfaction of desire). Aristotelians see the process of moral growth as in large part a process of making one's feelings, emotions and desires conform to moral reality--feeling to do virtuous deeds and all that.
On the other hand, there are significant strands of the Christian spiritual tradition that say that feelings, emotions and desires are irrelevant at least for those who are no longer beginners in the spiritual life (e.g., St. John of the Cross), or bad since they distract us from purely spiritual contemplation (e.g., many but not all the Desert Fathers). And much of the Christian spiritual tradition recognizes feelings, emotions and desires as often dangerous and distracting. It is tempting to dismiss these pronouncements as flowing out of a mistaken view of human nature, out of neo-Platonic intellectualism, and sometimes these pronouncements do indeed thus flow, but it is worth remembering that many of the spiritual writers are very empirical. They see in their own lives and the lives of others around them what works and what does not work in the task of submitting every deed and every thought to God, of doing everything out of love alone.
I do not dispute the claim that human perfection includes perfection of the emotions, feeling and desires, that it is good to feel compassion for the suffering, that it is good to desire what is good and to desire to avoid evil, that it is good to enjoy virtuous activity, and all that. But I think we need to be careful to hold on to the truths contained in the parts of the spiritual tradition that are much more cautious in approaching to the emotional life, especially in light of how empirically grounded the wisdom of this tradition is. The Desert Fathers were not theoreticians--they lived in the desert, they weaved baskets, they struggled with temptation, they guided and were guided.
In our fallen state, our feelings and desires do lead us astray. Making a habit of visiting friends out of the pleasure of their company, rather than out of the duty of friendship, may well make it more probably that we will not visit them when the visit is not pleasant. The six lesser deadly sins--lust, gluttony, greed, sloth, wrath and envy--are all grounded in particular emotions. And at least some instances of pride are so as well. Now it is possible to fight these deadly sins by developing a more balanced emotional life, fighting gluttony with a deep emotional appreciation of moderation, fighting sloth by developing a balanced appreciation of good work, and so on, and indeed in the state of human perfection the virtues opposed to the deadly sins would have such emotional components, it is far from clear that this is the most effective way of fighting the deadly sins. It may be for some of them--thus, developing an appreciation of goods happening to others might be the best way to fight envy. But for others, something like the ideal of ataraxia, being unmoved by feelings and pleasures, might be rather more effective.
And then there is the wisdom of John of the Cross. Popular stereotype would not make one think of this passionate Spanish mystic as a defender of the centrality of reason to the Christian life. But in five separate Sayings of Light and Love, St. John indicates that what is most pleasing to God is that we act in accordance with reason, regardless of our feelings. And this is essential once one recognizes--as the lives of holy men and women like John of the Cross and Teresa of Calcutta abundantly show--that a dark night is a crucial part of spiritual maturation, a night in which most of the feelings that move the beginner in the spiritual life are absent. In the dark night, if one is to survive, one has no choice but to do what is right by reason, which reason is enlightened by the dark light of faith.
Feelings, emotions and desires are useful to the beginner in both the spiritual and the moral life. In the spiritual life, they make easy sacrifices that need to be made, which sacrifices one is not yet mature enough to make on the grounds of reasonable love alone. Love, of course, is not a feeling, emotion or desire--it is a committed determination of the will towards the good of and union with the beloved. There are emotions characteristic of love, but they are not always present with love. In the moral life, we may need moral feelings to help us come to the truth about things. Our repulsion at killing may help us come to accept that we ought not to commit murder. Altruistic helpfulness may help us to come to accept that we have duties towards neighbor. But once we have the truth about the moral life, this helpfulness is radically diminished, and the fallible emotions may in fact often be more harm than good, at least in this earthly life. (And, of course, if we have the Catholic faith, then we basically have the truth about the central aspects of our moral life, and we can derive many other truths from that.)
So I think that the Desert Fathers who embraced ataraxia--"affectlessness", we might translate it--as an ideal were wrong about human nature as it is ultimately meant to be, but it is far from clear that they were wrong, or at least far wrong, about the best way to proceed given what fallen nature is like.