“Fasting repels Sinful Thoughts”
– Imam al-`Izz Ibn `Abd Al-Salam
“As for fasting repelling sinful thoughts and bad behaviour, this is because if the nafs [s: appetites, lower self; ego-soul] is gratified or satiated, it inclines towards and directs itself to disobedience as well as bad behaviour. If it is made to feel hungry or thirsty, it will long for food and drink. The inclinations and desires of the nafs towards spirituality and to busy it with that is better than its inclination towards and desire for disobedience and lapsing into sin. This is why some of the Salaf preferred fasting over the other acts of worship. One was asked about that and he replied: ‘because I would prefer Allah looking at my nafs while it is in conflict with me over food and hunger than when it is in conflict with me over disobedience to Him [after] having been satiated…”
قدم بعض السلف الصوم على سائر العبادات فسُئل عن ذلك فقال: لأن يطّلع الله على نفسي وهي تنازعني إلى الطعام والشراب أحبّ إليّ من أن يطّلع عليها وهي تنازعني إلى معصيته إذا شبعت
- Fasting is a preventative measure – it stops a person from committing a certain action.
- Fasting is a controlling mechanism, i.e. it restrains a person and restraint is what is required in order to combat one’s desires.
- Fasting is one of the most beloved actions to the early paragons of piety in that they would prefer Allah examining them and looking at their nafs while it was in a state of conflict due to hunger and thirst rather than when it is satiated. When one is satiated and satisfied, the inclination and agitation to commit sin weakens as opposed to when the nafs is disturbed and activated.
 Imam al-`Izz Ibn `Abd al-Salam, Maqasid al-Sawm, p.17.