The word Sawm or fasting comes from the Arabic root word ‘Sawma’ which means to keep silent. The Qur’aan uses the word generally when it revealed the conversation between the angel and Mayam (AS) [Mary], the of mother of Eesaa (AS) [Jesus], as the angel instructed her “And if you do see any man say, “I have vowed to remain silent for Allah”. (al-Qur’aan 19:26)
Although the definition indicates restraining the stomach and private parts, the tongue, eyes, ears and other limbs should equally be restrained if the fasting person wants to gain the total rewards of fasting. This is why Rasoolullah (SAW) has been reported as saying in a hadith by Abu Hurairah (RA) “He who does not desist from obscene language and acting obscenely (during the period of fasting), Allah has no need that he be hungry or thirsty.” (Bukhari Muslim)
In another hadith by Abu Hurairah (RA), Rasolullah (SAW) said: “Fasting
is not only to restrain from food and drink, fasting is to refrain from obscene (acts). If someone verbally abuses you or acts ignorantly towards you, say (to them) ‘I am fasting, I am fasting.'” (Ibn Khuzaimah)
It is compulsory to restrain private parts and the stomach from food and drink but one should also restrain the jawarih, the other body parts to get the maximum reward and spirituality of fasting. Otherwise the fast will be worthless despite the main factors of hunger and thirst. What folly to fast the entire day without gaining a single reward!
The tongue, for instance, must avoid backbiting, slander, and lies, the eyes should not look at anything considered unlawful, the ears must not listen to lewd and useless conversations, music and lyrics that spoil the spirit of fasting.
The heart and mind should not indulge themselves in other things besides dhikr Allah (remembrance of Allah).
So the entire body should observe discipline in order for the rooh (soul) to be spiritually nurtured. For it is indeed the soul that is everlasting, the body is merely a vehicle for the soul.