It was said that we fast to understand and feel the suffering of the poor and share their needs, but this concept is wrong. We don’t fast for this purpose, but we fast to be righteous, inwardly and outwardly. We fast as whatever Allah’s Command is, we should follow it. Islam is based on the idea of ”And obey Allah and the Messenger (Muhammad SAW) that you may obtain mercy” ( وَأَطِيعُواْ ٱللَّهَ وَٱلرَّسُولَ لَعَلَّكُمۡ تُرۡحَمُونَ) Surah Āl-‘Imrān. That is why we repeatedly assure that doing the obligatory deeds and Sunnah deeds doesn’t need a logical justification. We do the goodness because Allah has said so. No Muslim shall have any doubts regarding the fact that when you obey the Prophet Muhammed, you obey Allah too. When you do the Prophet’s Muhammed Sunnah, you obey Allah. Fasting Mondays and Thursdays is a SUNNAH.
The Sunnah gets us closer to the Prophet Muhammed, he said about fasting on Mondays and Thursdays,
Abu Huraira reported Allah’s messenger as saying,
“Men’s deeds are presented [to God] on Mondays and Thursdays, and I like mine to be presented when I am fasting.”
When you voluntarily fast, you show your absolute obedience to Allah and your desire to gain the rewards. For fasting for Allah’s sake has an infinite reward. Allah (swt) says, “Fasting is Mine, and I am the one who rewards it.” You decide to leave your food, drink and the sexual drive for sake of Allah and that is why Allah gives us unlimited rewards. You train the self by abstaining from sinful deeds to control your thoughts and desires. By fasting you benefit your mind, body and heart. Remember that the Prophet Muhammed’s said that there are three whose supplications are not turned back, one of them is a fasting person until he breaks his fast, and this goes with the obligatory and Sunnah fasting.
Following the good example of the Prophet (SAW) should be enough to convince you about fasting the Mondays and Thursdays. For Monday, it was the day when the Prophet Muhammed was born. We remember our beloved prophet’s birth on this day. If you can not fast the two days, you can fast one day, and Allah makes things easy for us as Muslims. Fasting on Monday and Thursday is a sunnah, which means that if the Muslim leaves this sunnah, he/she will not be sinned but if the fasting is done, a great reward is waiting for him/her. So why would anyone intentionally leave this great deed and this great reward!