Love and Desire, i see them as two different ways of life. Love as being from the heart, spirit; and desire coming from the mind, or what we call ego.
Love is the easy way, the natural path to live, because it is in harmony with all that exists. Desire is a path dotted with pain.
The love for Christ and the desire of atonement
In this title, Love and Desire can appear the same, towards the same thing; but they are very different.
The one that loves Christ, follows and listens to his teachings, of course will attain atonement because what he does has enthusiasm. But when there is only the desire for atonement it involves most of the times suffering. For example, the Church says that it wishes the salvation of humanity, but uses methods through which a person suffers both physically and mentally if he follows them as they want to be followed , such as fasting by a calendar, or the so-called canons.
Those that live in a monastery with the desire for atonement submit to different laws, labours and restrictions that cause them displeasure and pain.
Therefore doing something out of love or out of desire, i see them as two different and contrary paths. The love for Christ (for his teachings) leads you to atonement, there is no need to have in your mind the desire for salvation, because your spirit already knows it is happening, but when there is a desire for atonement, it implies a selfish purpose.
The love for to be healthy and the desire to be healthy
Also in this context Desire can seem positive, but at a close look, you can see it comes from a negative character.
When you have something, there is no need to desire it, but the desire to be healthy implies the lack of this state.
The person that lives lead by such a mental desire feeds himself /heself with various supplements, vitamin pills, follows different diets; but these are the things that affect your body and maintain that sick part that desires to be healthy, but only "faked" because in it`s subconscious it wants to maintain the state of something that desires to be healthy (meaning the disease).
But the person that loves to be healthy has no need and does not feel the desire to be healthy, because the love within him makes him choose a healthy life, to live healthy, he cares about his body, mind and soul, and his life style guided by this love maintains him healthy without feeling or doing any special effort in this way.
The love for life and the desire to live
The desire to live can appear as something positive, normal; but it is selfish, it is not in harmony with everything that is life, it is from fear of death. And where there is fear, there is suffering.
The one that has love for life, lives by nature in harmony with all the life around him, and life loves him and helps him to live happily without having his own desire for that.
Here is an example that shows more clearly what I mean.
A man was lost in a desert. After some time seeking for water and some food, he saw a goat. Although quite exhausted, he managed to catch it, and, blinded by the desire to live, killed the goat to feed with it, thinking he would live until he will be rescued. But the body rotted and that man, soon after, died.
In the same desert another man was love, generous, with a love for life. Seeking for water and a source of food he also saw a goat and managed to catch it. Having a love for life, he didn't think to kill it, and the sacred spirit inside him gave him wisdom on what to do. He milked the goat, drank the milk and recovered his strenght. He freed the goat and followed it to see how it lived in that desert. That is how he found a small cave where moisture was produced from condensation, and from that mushrooms grew from which the goat would feed. He lived there with the goat, feeding with the goats milk until he was found by those that were looking for him. That is how he lived, not because of the desire to live, but thanks to the love for life.
Love and desire can be on all levels, and things; love is the easy path, beautiful because it`s natural, in harmony with all that God has created that is love. On the other hand desire is something personal, selfish, not in spiritual harmony with what is around it, and thus leads to suffering.
For example, a child that desires to be good at Math, is preoccupied with having good grades, makes an effort to learn how to solve mathematical problems; preoccupation that has behind it the fear of failing, and to not fulfill them gives birth to frustration and suffering.
On the other hand, a child that loves Math, learns easily, and being out of passion, is less interested in grades, which will save him from feeling frustrated.
Loving is living with joy in the present, in the now; but desire becomes a purpose, something to achieve in the future, and that separates you from the present moment that it is the life itself.
Every one of us has pure love in them, but it is covered with all kinds of desires to have, to do, etc., implemented in our mind by society and an educational system that promotes /cultivates the idea of always desiring something.
In order to discover and to let this love resurface, that layer of mental desires, that have become a part of ourselves must be pushed aside; as Christ teaches: "Let us forswear of ourselves".