Purpose of Fasting
The Qur'an says: (O you who believe, fasting is prescribed for you as it was prescribed for those who were before you, in order that you may learn taqwa. ) (al-Baqarah 2: 183)Taqwa is a very important spiritual and ethical term of the Qur'an. It is the sum total of all Islamic spirituality and ethics. It is a quality in a believer's life that keeps him/her aware of Allah all the time. A person who has taqwa loves to do goodTaqwa is piety, righteousness and consciousness of Allah. Taqwa requires patience and perseverance. Fasting teaches patience, and with patience one can rise to the high position of taqwa.
The Prophet (peace and blessings be upon him) said that fasting is a shield. It protects a person from sin and lustful desires. When the disciples of Jesus asked him how to cast the evil spirits away, he is reported to have said, "But this kind never comes out except by prayer and fasting.” (Matthew 17:21). 
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