Prayer - "A Time of War"
We find in the Zohar that prayer is compared to a time of war. One may ask: “Against whom does this war take place?” The answer is: “Against oneself”. But what is the purpose of this war, and how does one fight it?
Before answering these questions, we must first explain the inner makeup of man.
Man is comprised of a body and a soul. His body, which was formed from the earth, has a nefesh [life force] from which it receives its vitality. This force is called the vital or animal soul. This aspect of man is almost exclusively interested in the physical pleasures of the world.
In contrast, man’s Divine soul comes from the highest heavenly realm, carved out from under God’s throne of glory. It is this soul that G-d breathed into man, as it is written: “And He [G-d] blew into his nostrils the soul of life, and man became a living being.”
Body and soul are represented homiletically in the story of Yaakov and Eisov, Yaakov representing the soul, and Eisov representing the body. Just as they were at odds with one another ― Eisov, a creature of this world, and Yaakov, devoted to a life of Torah and spirituality ― so too, the physical and spiritual facets of man are at odds with one another, each pulling in opposite directions. When one prevails, the other falls.
Winning the Battle
The inner purpose of prayer is to do battle against one’s animalistic pulls, and selfish desires. Through its meditative process a person can rise above one's physical and material existence to which he has become accustomed, attaining a superior level of refinement, and a true level of sanctity and purity. Although one doesn’t always see quick results, through continued prayer (three times a day) a person will improve his spiritual standing.
According to the above, we can understand why prayer is called avodah [work], which can be understood to represent the work in the Beit HaMikdash, namely, the daily sacrifices, as the Sages taught: “The prayers were instituted in place of the daily sacrifices.”
According to Chassidic philosophy the offering up of animals on the altar represents the transformation of one’s animal soul. Thus, a person who offered up an animal was meant to imagine that he himself was being slaughtered and consumed by the fire. Today, this is accomplished through the service of prayer. When one concentrates deeply on the words of prayer, arousing within the heart a longing to draw close to G-d above, even the body becomes consumed by the joy and pleasure of Divine worship.