‘Awf, who said: O Messenger of Allah, you have encouraged us to use the siwak [is there anything beyond that] (25)? He replied: "Your two fingers are a siwak when you perform your wudu; pass them over your teeth. Indeed, there is no action for one who has no intention, and no reward for one who has no good deed."
15 - Issue: He said: (Unless he is fasting, in which case he should refrain from the time of the Dhuhr prayer until the sun sets).
Ibn ‘Aqil said: There is no disagreement within the madhhab that using the siwak after the sun has passed its meridian (zawāl) is not recommended for the fasting person. Is it disliked? There are two reported views: One of them is that it is disliked, which is the opinion of al-Shafi‘i, Ishaq, and Abu Thawr. This is also reported from ‘Umar, ‘Ata’, and Mujahid, based on what was narrated from ‘Umar, may Allah be pleased with him, that he said: "One may use the siwak between [the beginning of the day] and Dhuhr, but he should not use it after that." Another reason is that the siwak was only recommended to remove the odor of the mouth, and the Prophet (peace and blessings of Allah be upon him) said: "The odor of the mouth of a fasting person is better in the sight of Allah than the scent of musk" (28). Al-Tirmidhi said: This is a hadith...
(25) Omitted from the original (al-Asl). (26) Thus in the copies, and it is likely based on the estimation: "They (the two fingers) are a siwak." (27) In manuscript M: "No." (28) Recorded by al-Bukhari, in: The Chapter on the Virtue of Fasting, and the Chapter on Whether One Should Say 'I am Fasting' if He is Abused, from the Book of Fasting; in: The Chapter on What is Mentioned Regarding Musk, from the Book of Clothing; and in: The Chapter of His Saying the Almighty: {They want to alter the words of Allah}, and the Chapter on Muhammad ibn Abd al-Rahim narrating to me, from the Book of Tawhid. Sahih al-Bukhari 3/31, 34, 7/211, 8/175, 192. Muslim, in: The Chapter on the Virtue of Fasting, from the Book of Fasting. Sahih Muslim 2/806, 807. Abu Dawud, in: The Chapter on the Virtue of Fasting, from the Book of Fasting. Sunan Abi Dawud 2/24. Al-Tirmidhi, in: The Chapter on What Has Been Reported Regarding the Virtue of Fasting, from the Chapters on Fasting. ‘Aridat al-Ahwadhi 3/294. Al-Nasa’i, in: The Chapter on the Virtue of Fasting, the Chapter on the Disagreement Regarding Abu Salih, and the Chapter on the Disagreement Regarding Muhammad ibn Abi Ya‘qub. Al-Mujtaba 4/132, 134-136, 139. Ibn Majah, in: The Chapter on What Has Been Reported Regarding the Virtue of Fasting, from the Book of Fasting. Sunan Ibn Majah 1/525. Al-Darimi, in: The Chapter on the Virtue of Fasting, from the Book of Fasting. Sunan al-Darimi 2/24. Imam Malik, in: The Chapter of Miscellaneous Fasting, from the Book of Fasting. Al-Muwatta’ 1/310. Imam Ahmad, in: Al-Musnad 1/446, 2/232, 234, 257, 266, 273, 281, 292, 306, 307, 313, 347, 393, 395, 407, 411, 414, 443, 457, 458, 461, 465, 467, 475, 477, 480, 485, 501, 504, 505, 516, 532, 3/5, 40, 4/130, 202, 6/240.