Fasting establishes supremacy of the soul
The preponderance of animality in man is an obstacle in the path of the manifestation of angelic and celestial attributes. Therefore, it has become necessary to subjugate this attribute of animality in man.
Since the dominance and power of bestial attributes are caused by eating, drinking and excessive indulgence in lowly desires – the latter playing the dominant role in the assertion of bestial attributes – it is essential to curtail and curb the onslaught of the flesh by a reduction in these factors (eating, drinking and indulgence in desire). Precisely for this reason do we find unanimity among all those who desire the supremacy of the soul and the subjugation of the flesh. All such men are unanimous in their assertion that the method of establishing the supremacy of the soul over the body is to reduce indulgence in eating, drinking and lowly desire. A remarkable fact is that this unanimity exists despite the different religions and lands of these men (i.e. those who desire the supremacy of the soul). It is of prime importance that the animal body remains within the power and control of the higher soul so that it (the body) becomes infused with the nobility and transcendence of the higher soul. It is likewise essential that the celestial soul remains aloof of the flesh in a way that will protect it from coming under the sway and control of the animal body. There is no better method of asserting the supremacy of the soul over the body than denial of the material and animal wants and desires of the body. Self-denial compels the animal body into obedience and submission of the celestial soul. Material dictates and animal desires are attributes of the animal self, therefore, by self-denial man aligns himself with the angelic realm. And, this purpose is achieved by means of fasting.
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