Fasting is one of the five pillars of Islam. The verses of Al-Quran and Hadith regarding fasting are presented below:

O believers! Fasting has been prescribed for you, as it was prescribed for those before you, so that you may adopt taqwa or fear Allah.’ (Surah Baqara, verse-183)

Fasting is for a certain number of days. If one of you is sick or on a trip another time will fill this number. It is the duty of those for whom it is too painful to give fidiya – food to a needy person instead. If one does good deeds spontaneously, it is more beneficial for him. And fasting is better for you if you know it. (Surah Baqarah, verse 184)

The month of Ramadan, in this month the Qur’an was revealed as a direction of light and a clear sign of the right path and a distinguisher of the truth. So those of you who receive this month should fast in this month, and if someone is sick or on a journey, he should make up this number at another time. Allah desires for you that which is easy and He does not desire for you that which is difficult, that He may fulfill your number and that you may glorify Him by guiding you and that you may express gratitude.’ (Surah Baqarah, verse 185)

Your wives have been made lawful for you during the night of fasting. They are clothing for you and you for them. Allah knows that you were betraying yourselves, then He accepted your repentance and forgave you, so now join them and seek what Allah has ordained for you (i.e. children). And eat and drink until the white line of dawn becomes clear to you from the black line (of night). Then complete the fast till night. And do not associate with them in the state of I’tikaf in the mosque. These are Allah’s (ordained) limits, so do not come near them. This is how Allah explains His verses clearly for people, so that they may adopt taqwa or fear of Allah.’ (Surah Baqarah, verse-187)

Narrated from Hazrat Sahl bin Sa’d (RA). He said, The Messenger of Allah (peace be upon him) said, There is a gate of Paradise, it is called Rayyan. Through this door, on the Day of Resurrection, only the fasting person will enter Paradise. None but them shall enter this way. On that day it will be called – Where are the fasting people? May they enter this way. In this way the door will be closed after all the fasting persons have entered. After that, no one will enter this path.’ (Sahih Bukhari-1896, Sahih Muslim-1152)

Narrated from Hazrat Abu Huraira (RA). He said, Rasulullah (SAW) said, Fasting is like a shield. If any of you ever fasts, let no obscene words come out of his mouth. If someone insults him or wants to provoke him into a quarrel, let him say, I am a fasting person.’ (Sahih Bukhari- 1894, Sahih Muslim- 1151)