"To love G‑d, your G‑d, and to serve Him with all your heart."

This is the classical proof-text for prayer, as cited earlier. That verse, however, has more words: "with all your heart and with all your nefesh."

Nefesh is usually translated as 'soul' or 'life' (and the literal meaning of the verse thus implies a readiness for self-sacrifice.

Even so, the term nefesh may also mean - and in various passages is interpreted as - 'will'.

This second meaning applies also to our definition of prayer. Thus we can now rephrase our proof-text to read "To serve Him with all your heart and all your will" - this is prayer.

This is not a far-fetched or arbitrary interpretation when considering that the total submission (and thereby: sublimation) of will is the very purpose of prayer.

The ideal of the Mishnaic dictum "Nullify your will before His will" is the aim of, and becomes realized through, prayer. Tefilah requires and must effect a state of "All my limbs shall say, 'G‑d, who is like You!'" (Psalms 35:10). For tefilah is to involve man wholly and totally: all wills and desires must be subjected to His, the Divine Will.

The very essence of tefilah thus implies bitul hayesh, to negate and nullify all traces of ego, of self-centeredness.

Prayer demands a transcendence of self, "as if stripped of physicality, no longer sensing one's own reality in this world."

"Man must regard himself as ayin (naught) and forget about himself altogether..". Thus he is able to transcend the temporal and enter the 'world of thought' where everything is the same: life and death, sea and land.. If one remains bound to the materialism of this world, one is bound to the diversity of good and evil; how, then, can he transcend the temporal to the sphere of absolute unity and oneness?

Moreover, when assuming selfhood and concerned with personal needs, the Holy One, blessed be He, cannot be vested in him; for He, blessed be He, is En Sof (Infinite), thus cannot be held by any vessel. It is different, however, when regarding oneself as ayin (naught).

In this sense, too, tefilah is said to have taken the place of the Scriptural sacrifices.

On the altar of tefilah one is to offer the animal soul and nature of man. The natural desires and inclinations of the heart and the body are to be refined and purified to the point of exclusive concern with the necessary and proper.

The appetitive powers of the animal soul are to be directed towards the Divine, to seek Its nearness and to desire absorption therein.

Prayer will thus remove man from anything improper, even while motivating the practice of that which is just and right. That is how tefilah helps and leads to self-sanctification, not only in matters of chiyuv (incumbent obligations) and issur (incumbent prohibitions), but also in matters of reshut (the optional) - of 'may' and 'need not.'