The Beloved and Blessed Nabi صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم said: ‘مَنْ لَّمْ يَدَعْ قَوْلَ الزُّوْرِ وَالْعَمَلَ بِهٖ فَلَيْسَ لِلهِ حَاجَةٌ فِيْ اَنْ يَّدَعَ طَعَامَهُ وَشَرَابَهُ’, i.e. one who does not give up telling a lie (i.e. evil conversation) and acting accordingly, so Allah عَزَّوَجَلَّ does not need him remaining hungry and thirsty at all. (Sahih Bukhari, vol. 1, pp. 628, Hadees 1903)
Sawm is an act of worship performed physically. By its blessing, one can protect oneself not only from apparent sins but also from inner ones. If a person apparently gives up eating and drinking things but he does not protect himself form sinful acts, he cannot achieve the aim of Sawm. For the very same reason, it was said that Allah عَزَّوَجَلَّ does not need him remaining hungry and thirsty at all. This person gives up Halal [lawful] things but does not protect himself from Haraam acts (such as lying, backbiting, tale-telling, missing Salahs, watching movies and dramas, unlawful gazing and cheating others, etc.). So, what is the benefit of his Sawm?
Commenting on the above Hadees, the commentator of the book Sahih Bukhari, ‘Allamah Badruddin Mahmood ‘Ayni رَحْمَةُ اللهِ تَعَالٰی عَلَيْه stated: If, even in the state of Sawm, a bondman does not give up telling a lie and acting accordingly which are among the biggest of all big sins, so he should ponder how he is dealing with his Sawm. (‘Umda-tul-Qaari, vol. 8, pp. 34, Taht-al-Hadees: 1903; summarized)
‘Allamah ‘Abdur Ra`oof Manaawi رَحْمَةُ اللهِ تَعَالٰی عَلَيْه stated: This Hadees does not mean that the person unable to protect himself from sins should not keep Sawm but rather its purpose is that he should give up sins. (Sharh Bukhari li Ibn Bataal, vol. 4, pp. 23, Taht-al-Hadees: 1903)
‘Allamah Ibn Rajab Hanbali رَحْمَةُ اللهِ تَعَالٰی عَلَيْه stated: The secret behind it is that one can gain closeness in the Divine court by refraining from Mubah acts such as eating and drinking things and from intercourse provided that he also protects himself from Haraam things. Therefore, whoever tries to gain the closeness of Allah عَزَّوَجَلَّ by giving up only Mubah things despite committing Haraam deeds is like the person who attempts to gain the closeness of Allah عَزَّوَجَلَّ by means of Nafl deeds despite missing Fard ones. (Al-Lataaif-ul-Ma’arif, pp. 179)
A great thinker of Ummah, Mufti Ahmad Yar Khan رَحْمَةُ اللهِ تَعَالٰی عَلَيْه stated: Telling a lie here implies every type of impermissible conversation including lying, false accusation, backbiting, tale-telling, swearing, cursing etc. It is Fard to protect oneself from them. And the evil deed here means every impermissible deed committed whether by the eye, the ear, the hand or the foot, etc. As the sins committed by the tongue are larger in number compared to the ones committed by other parts of the body, therefore, they were separately mentioned. This is a very comprehensive Hadees in which all things were described only in two sentences. In every situation, evil deeds are always bad but they are considered even worse if committed in the state of Sawm as committing them is dishonour for Sawm and disrespect for Ramadan. Therefore, Sawm was particularly mentioned. There is one punishment for committing one sin anywhere else but if one sin is committed in Makkah Mukarramah, so there are one hundred thousand punishments for it. Why? Because of disrespect for the holy land.
He رَحْمَةُ اللهِ تَعَالٰی عَلَيْه further stated: The Arabic word ‘Haajah’ [حَاجَة] mentioned in the Hadees does not actually mean any need because Allah عَزَّوَجَلَّ is free from needs [i.e. He never needs anything]. In fact, it here implies that Allah عَزَّوَجَلَّ does not accept the Sawm of such a person. If the Sawm is not accepted, so it is as if one only remains hungry. It also hints that even though this Sawm is valid by Shari’ah and Fard obligation will get fulfilled but it will not be accepted. Conditions for the validity of Sawm only include making intention and giving up eating, drinking and intercourse but conditions for the acceptance of Sawm include giving up indecent conversation and evil actions. This is the real aim to be achieved by observing Sawm. The purpose of Sawm is to break the power of one’s Nafs, which results in giving up sins. If sins are not given up in the state of Sawm, so it shows that Nafs is not suppressed. Respected Sufis say that Sawm of every part of the body should be observed. Besides giving up Halal things such as eating and drinking items, you should also give up Haraam acts such as lying and backbiting, etc. It is stated in the book Mirqat that although such an incautious Sawm-observer will be given reward for the actual Sawm, yet sin for those evil actions [will also be recorded for him]. (Mirat-ul-Manajih, vol. 3, pp. 158, 159)