Desire and love are the two opposing forces between which the soul develops

 

Wisdom is better than rubies,
and all the things that may be desired
are not to be compared to it.

— Proverbs 8:11

Rudolf Steiner:   "The soul is initially a desiring being. The soul is filled with sympathy and antipathy, with the world of desires, with the world of longing. But after a while, the spirit shows the soul that it does not have to merely desire. When the soul has overcome desire through the decision of the spirit, it is not idle; just as desire flows from the undeveloped soul, love flows from the developed soul. Desire and love are the two opposing forces between which the soul develops. The soul still entangled in sensuality, in outward form, is the desiring soul; the soul developing its connection, its harmony with the spirit, is the one that loves. This is what guides the soul in its course from rebirth to rebirth: that it becomes a loving soul from a desiring, longing soul — that its works become works of love."

Source: The Rudolf Steiner Archive March 8, 1904