It is narrated from Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) that "the Prophet (peace and blessings be upon him) forbade forming circles (in the mosque) on Friday before the imam comes out (for the sermon)."
Abu Hafs Amr bin Ali (may Allah have mercy on him) said: I heard al-Mu'tamir bin Sulayman (may Allah have mercy on him) say that Yahya bin Sa'id al-Qattan (may Allah have mercy on him) narrated this hadith to us. (The narrator said:) I asked Abu Hafs: "Did you hear this hadith from Yahya?" He replied: "More than a hundred times."
Abu Hafs (may Allah have mercy on him) narrates: I saw Abd al-Rahman bin Mahdi (may Allah have mercy on him) come on Friday before the prayer to the study circle of Yahya bin Sa'id and Mu'adh bin Mu'adh (may Allah have mercy on them both), and he sat down outside the circle. Yahya bin Sa'id (may Allah have mercy on him) said to him: "Come inside the circle." Abd al-Rahman (may Allah have mercy on him) said to him: "Was it not you who narrated this hadith to me with the chain of Muhammad bin Ajlan, from Amr bin Shu'ayb, from his father, from his grandfather, that the Messenger of Allah (peace and blessings be upon him) forbade forming circles on Friday before the imam comes out?" At this Yahya bin Sa'id (may Allah have mercy on him) replied to him: "I have seen Habib bin al-Shahid, Hisham bin Hassan and Sa'id bin Abi Arubah (may Allah have mercy on them) forming circles on Friday before the imam came out." Abd al-Rahman (may Allah have mercy on him) said: "Had it reached these people that the Messenger of Allah (peace and blessings be upon him) forbade (forming circles) on Friday, and yet they still formed circles?" Hearing this, Yahya bin Sa'id (may Allah have mercy on him) fell silent.
No one narrated this hadith from al-Mu'tamir and Abd al-Rahman bin Mahdi, from Yahya bin al-Qattan, except Abu Hafs.