It is reported that ʿAlī – Allāh be pleased with him – said:
When you learn knowledge, preserve it, and do not mix it with laughter and falsehood, such that the hearts refuse (dislike) it.
Al-Khaṭīb Al-Baghdādī, Al-Jāmiʿ li-Akhlāq Al-Rāwī wa Ādāb Al-Sāmiʿ 1:232
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The Salaf used to be careful not to speak in front of elders unless absolutely needed.
It is reported that Abū Bakr Al-Maṭū’ī said: I sat in the circle of Abū ‘Abdillāh Aḥmad b. Ḥanbal for twelve years while he read the Musnad to his children, and I never wrote a single ḥadīth, I only looked at his behavior, character and etiquette. Ibn Al-Jawzī, Manāqib Aḥmad, article 210. It is reported […]
It is reported that there was a young man who was from the people of knowledge who used to put himself forward, speak and behave haughtily with his knowledge in front of those older than him. This angered Sufyān [Al-Thawrī] and he said, “The Salaf were never like this; they never used to claim leadership, […]