Al-Kāfi
Hadith 2178مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدِ بْنِ عِيسَى عَنْ مُحَمَّدِ بْنِ خَالِدٍ وَ الْحُسَيْنِ بْنِ سَعِيدٍ جَمِيعاً عَنِ الْقَاسِمِ بْنِ عُرْوَةَ عَنْ إِسْحَاقَ بْنِ عَمَّارٍ عَنْ أَبِي عَبْدِ اللَّهِ ( عليه السلام ) قَالَ السِّوَاكُ مِنْ سُنَنِ الْمُرْسَلِينَ .
2. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad ibn ‘Isa from Muhammad ibn Khalid and al-Husayn ibn Sa‘id all from al-Qasim ibn ‘Urwah from Ishaq ibn ‘Ammar who has said the following: “Abu ‘Abd Allah (a.s.), has said, ‘Brushing one’s teeth is of the Sunnah and moral discipline of the prophets.’”