Fasting - Worship

"0 you who believe, fasting is prescribed for you as it was prescribed for those that were before you, so that you may be godfering. (Fast) A certain number of days. But whoever of you is sick or on a journey, then (he shall fast) the (same) number of other days and for those who are able(with hards-hip to fast) a redemption by feeding a needy poor person. But whoever volunteers to do good it is better for him; and to fast is better for you,if you know.

The month of Ramadhan in which the Qur'an was sent down to be a gyidance for mankind and as clear signs of guidance and a criterion (between right and wrongl. Therefore, whoever of you is present at the month, fast it; and whoever is sick, or on a journey, then (fast) the (same) number of other days; Allah desires ease for you, and desires not hardship for you; so that you should complete the nwnber (of days decreed), and exalt Allah for His guiding you, so that you might be thankful." 

Holy Qur'an (2 :183 - 185)