Mishkat al-Masabih 3 Purification كتاب الطهارة 90

عَنْ عَائِشَةَ قَالَتْ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «السِّوَاكُ مَطْهَرَةٌ لِلْفَمِ مَرْضَاةٌ لِلرَّبِّ» . رَوَاهُ الشَّافِعِيُّ وَأَحْمَدُ وَالدَّارِمِيُّ وَالنَّسَائِيُّ وَرَوَاهُ البُخَارِيّ فِي صَحِيحه بِلَا إِسْنَاد

‘A’isha reported God’s messenger as saying, “The tooth-stick is a means of purifying the mouth, and is pleasing to the Lord.” Shafi‘i, Ahmad, Darimi and Nasa’i transmitted it, and Bukhari transmitted it in his Sahih without an isnad .