What does the occultist mean when he says we should endeavor to kill out desire? He does not mean that we should do away with the driving power in life. Desire is the motive force that sends the Universe along.
Unfortunately it has been my experience in the Theosophical Movement to see some very worthy people reduced to complete inertia thinking they were really striving along the Path and had killed out desire — and the poor things had! But you cannot perform any duty in life without the principle of desire energizing your being. It is a vehicle for your will. So, in considering this question, there must be a particular sense in which desires have to be killed out. It is only those desires that intensify your material and transitory nature that have to be killed out. We have to change or transmute finite desires into aspiration. If you are a Christian you call it prayer, and true prayer, which is aspiration towards the spiritual part of your being, to the Supreme itself, doing all actions without a selfish desire for the fruit of those actions — this is the state towards which we aspire, difficult enough, but true. That is the use of desire.
But there is another way of looking at this question. The highest philosophical and metaphysical concepts that we study in a Theosophical Lodge take the mind into a region that is really beyond the region of desire, and that is why we study them. It is to purify the desire nature and free the mind from identification therewith, that we study philosophy and metaphysics. To quote a lovely phrase of Gautama Buddha: We try to teach the mind to walk in the way of Truth; we try to instruct our mental part, our true individuality, to recognize its essential oneness, unity, identity with the one Mind, the one Being which is the Universe, for it is the greatest mistake in the world if you think of the planet and the solar system, and the marvelous Universe of which it is a part, as something outside of you. You are part, an essential spark of its own life; part of its great river of being. So that we think of this Universe as a conscious living entity, we playing our little roles and parts in its gigantic term of life; and the purpose of the whole thing is to realize that there is not a moment of life when the atoms of the material part of us cannot be transcended and conquered by rising above desire into unity with the one mind, the Universal Soul, which incidentally is without bounds. Is that an idea that inspires you? If you have never thought of it before, dwell upon it, and think, for one of these days it will give you the greatest lift that it is possible for a philosophical idea to do, for then you will realize that you are not your weak and erring and sinful mind, but that if you are willing to rise above these things, to let them go out of your life, you have the power of the One Mind; you have the Life and the Knowledge and the Wisdom and the Truth of the Universal one Self, which is the same in you and in me.