12 – When the legal proofs appear to conflict—some implying obligation while others indicate mere recommendation, or some suggesting outright prohibition while others point only to dislike—and there is no established principle on which to base a ruling, the inherent leniency of the Sharīʿah, its policy of easing hardship for the servants, and the presence of broad, all-embracing texts tip the balance toward adopting the easier of the two views, the one furthest removed from both prohibition and obligation. Al-Bukhārī and Muslim relate: “Whenever he ﷺ was given a choice between two matters, he would choose the easier of the two.”

Difference among the scholars
The general purport of the ḥadith indicates that using the siwāk is recommended at all times for both the fasting and the non-fasting, whether at the beginning or the end of the day. No evidence restricts this generality to the time when one is not fasting, save his ﷺ statement: “The change in the breath of the fasting person is, in Allah’s sight, more fragrant than musk” (al-Bukhārī 5927; Muslim 1151). Yet this is not a clear proof, for the odor arises from the emptiness of the stomach, not from the mouth.

As for the report, “When you fast, use the siwāk in the morning and do not use it in the afternoon,” it is weak and contradicted by other ḥadiths—among them what Aḥmad (1525) and al-Tirmidhī (721), who graded it ḥasan, narrated, and what al-Bukhārī recorded in suspended form, from Kaʿb ibn Mālik: “I saw the Messenger of Allah ﷺ countless times using the siwāk while fasting,” without limiting it to any particular time of day.

Those who held that the siwāk remains recommended without qualification include the two Imāms Abū Ḥanīfah and Mālik; it was also the view preferred by Shaykh Taqī al-Dīn Ibn Taymiyyah, who said in al-Furūʿ that it is the stronger opinion.

Those who deemed it disliked for a fasting person after the sun has passed its zenith are the two Imāms al-Shāfiʿī and Aḥmad, their followers, and Isḥāq. They relied on the (weak) report, “When you fast, use the siwāk in the morning and do not use it in the evening,” and on the sound ḥadith, “The change in the breath of the fasting person is more fragrant to Allah than musk.” The latter, however, is not conclusive evidence, for the siwāk does not remove that odor; its source is the stomach, not the mouth.