Pillars & FiqhFasting the month of Ramadan is the fourth pillar; it is abstaining from the things that break the fast, from the break of dawn until sunset, as an act of worship to Allah, the Exalted. It is obligatory upon every sane, adult, and able Muslim, and whoever breaks the fast due to an excuse such as illness or travel must make up the number of days he broke.
Source:حديث جبريل، رواه مسلم؛ والبقرة: 185

