From the Benefits of Fasting

allah (the almighty) says:

{o you who believe, fasting has been prescribed for you as it was prescribed for those before you so that you may attain taqwa},

[soorah al-baqarah, ayah 183]. 

the messenger of allah (peace be upon him) said:

((fasting is protection)), i.e. protection from the fire of hell,

[the authenticity of this narration has been agreed upon by al-bukhaaree and muslim]

and he (peace be upon him) said:

((whoever fasts ramadan with eemaan while believing in its obligation and being hopeful for the reward, all that has preceded of his sins shall be forgiven)),

[the authenticity of this narration has been agreed upon by al-bukhaaree and muslim]

know! o muslim brother, that allah has prescribed fasting, and it is an act of worship which has many benefits, amongst them:

a) fasting allows the body's digestive system and the stomach to rest allowing the body to recuperate and strengthen. this is beneficial for many ailments. likewise, fasting allows the smoker to take a break from smoking and in doing so assists him in abandoning it.

b) fasting is a purification of the soul, and accustomising it upon good, worship, patience and sincerity.

c) the fasting person feels a sense of equality with the rest of his fasting brothers (and sisters); so he fasts with them allowing for the feeling of sincere islamic brotherhood to be nurtured. likewise, he feels hungry, as a result of which he gives charity to his hungry and needy brothers (and sisters).