Sufyan ibn Uyaynah رحمه الله said , on the authority of Imam Ibn Shihab al -Zuhri رحمه الله : I used to sit with Ali ibn al - Husayn ( Zain ul Abideen ) a lot and I did not see anyone who was more knowledgeable than him , but he spoke little . Tehzeeb ul Kamal volume 20 page 386
The Opportunity of Fasting Ashura
It is reported that Imām Al-Zuhrī – Allāh have mercy on him – was traveling and fasted ʿĀshūrāʾ, so he was asked:
“How comes you fast the Day of ʿĀshūrāʾ when traveling but not so during the fast of Ramaḍān?” He replied, “For Ramaḍān, the number of days can be made up later, but ʿĀshūrāʾ will be missed.”
Al-Bayhaqī, Shuʿab Al-Īmān ḥadīth 3518.
Also read
Related sayings.
Knowledge cannot be taken all at once.
Sometimes the manners you learn from a scholar surpass the piece of knowledge you get from him.