Here is the principle:

(Holy Spirit Byzantine Icon - found here)

“Not only must we be careful to want and desire good things for their own sake, but also to want and desire them in a way that is good. To be attentive not only to that which we want, but also to the way in which we want them. In effect, we very frequently sin in this fashion: We want something which is good, and even very good, but we want it in a way that is bad. . . .

We should . . . not only verify that the things we want are good in themselves, but also that the manner in which we want them, the disposition of heart in which we want them, are good. That is to say that our wanting must always be caring, peaceful, patient, detached and abandoned to God. It should not be an impatient wanting, hurried, restless, irritated, etc. In the spiritual life it is often there that our attitude is defective. We are no longer among those who want bad things that are contrary to God. Instead, from now on we want only those things that are good, in conformity with the will of God. But, we want them in a manner that is still not ‘God’s way,’ that is to say the way of the Holy Spirit, which is caring, peaceful and patient. We want them in a human way, tense, hurried and discouraged if we do not immediately achieve the desired goal.

All of the saints insist on telling us that we must moderate our desires, even the best of them. Because, if we desire in the human way that we have described, that will trouble the soul, make it uneasy, destroy its peace and thereby disturb God’s actions in it and in others.

This applies to all things, even to our sanctification. How many times do we lose our peace because we find that our sanctification is not progressing rapidly enough, that we still have too many faults? But this does nothing but delay things! Saint Francis de Sales goes so far as to say that ‘nothing retards progress in a virtue so much as wanting to acquire it with too much haste!’ . . .

To conclude, let us keep this in mind: As far as all our desires and our wishes are concerned, the sign that we are in accordance with truth, that our desire is in accord with the Holy Spirit, is not only that the thing desired is good, it is also that we are at peace. A desire that causes us to lose peace, even if the thing desired is excellent in itself, is not of God. It is necessary to want and desire, but in a free and detached way, in abandoning to God the realization of these desires, as He desires and when He wishes. To educate our own heart in this sense is of great importance for our spiritual progress. It is God Who converts us and causes us to grow, not our nervousness, our impetuosity and our impatience.”

~Jacques Philippe