The third pillar of Islam is Fasting, the essence of which is still unknown to people. The reality is that a person is unable to describe the condition of an area or state that he has never experienced.
Fasting does not mean that man should merely refrain from eating and drinking, it holds a far greater purpose and its effect can only be realised through experience. It is the innate nature of man that the less one consumes, the more purified the soul becomes and spiritual strengths accelerate. God desires through this that we decrease one form of diet and increase in another. A person who fasts should always bear in mind that the purpose is not to starve themselves, but to occupy themselves in the remembrance of God in order to develop in asceticism and self-discipline.
Thus, the essence of fasting is for man to limit himself from one form of nourishment (which nourishes the body alone) and attain other forms of nourishment, which satisfy the soul. Those who fast solely for the pleasure of God, and not just as a mere ritual, should occupy themselves in the praise, remembrance and adoration of God, which will ultimately provide them the other forms of nourishment.
(Malfuzat, Vol. 5, p. 102)