Sahih al-Bukhari 888

Arabic

حَدَّثَنَا أَبُو مَعْمَرٍ، قَالَ حَدَّثَنَا عَبْدُ الْوَارِثِ، قَالَ حَدَّثَنَا شُعَيْبُ بْنُ الْحَبْحَابِ، حَدَّثَنَا أَنَسٌ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ أَكْثَرْتُ عَلَيْكُمْ فِي السِّوَاكِ ‏"‏‏.‏

English translation

Narrated Anas:Allah's Messenger (ﷺ) said, "I have told you repeatedly to use the Siwak. (The Prophet (ﷺ) put emphasis on the use of the Siwak

Reference: Sahih al-Bukhari 888, Book of Friday Prayer. English translation by Dr. Muhammad Muhsin Khan.