حدثنا ابن أبي شيبة في كتابه كتاب الأدب من الجزء ما جاء في كف اللسان و خوف ما يكون من الكلام, عن وكيع عن سفيان عن عبد الله بن دينار عن ابن عمر قال: أحق ما طهر المسلم لسانه
Ibn Abī Shaybah relates to us in his work, The Book of Etiquette [Kitāb al-Adab], from the part, “What Is Said Concerning Withholding the Tongue as well as Fear Concerning Locquacious Speech”, by which we receive it on the authority of Wakī’, on Sufyān, on Abdullah Bin Dīnār, on Ibn Umar [may Allah be pleaed with him], who said:
“The most duty-bound thing a Muslim can clean is his tongue.“