Living As Spirit
Fasting is a symbol for the mind complex that is aware of the symbol that it is. Fasting can act as the symbol of ridding the soul, or, the mind/body/spirit complex, of excess and unwanted material via ridding the body of excess and unwanted material. Fasting can also be seen as symbolic of being sustained by The Infinite Creator's Original Focus (i.e., love).
Additionally, fasting can also acts as the stoppage of using external symbols in an attempt to fill an illusion of a void that one may feel due to negative thoughts; one can become more aware of the disharmonious feelings that certain thoughts generate within. This allows one a much greater chance to deal with these feelings instead of using foods as a distraction.
When we stop covering up the negative feelings of lack within us, we are more likely to be more aware of them. Once we are more aware of the negative feelings within the mind complex, we have a greater ability to choose/focus upon more peaceful feeling thoughts without the use of food or drugs that make it seem as if the feeling is no longer there when it still is.
All of this, and even more reasons, is what makes careful fasting, and/or some form of fasting a great spiritual practice. Fasting, in this sense, can act as a great step towards healing the soul, or, mind/body/spirit complex.