(Imām Bukhārī narrates): Yahya bin Bukair narrated to us, he said: Laith narrated to us from Uqail from Ibn Shihab, he said: Sa'id bin Al-Musayyab informed me, Hazrat Abu Hurairah (may Allah be pleased with him) informed him that the Messenger of Allah ﷺ said:

when you said to your companion on the day of Friday: Be quiet, while the Imam is delivering the sermon, then you have done a vain act.