The Prophet ﷺ said, "On Friday, angels stand at each of the doors of the mosque recording those who come, in the order they arrive. When the imam comes out, the records are folded up."
حدثنا سفيان عن الزهري عن سعيد
يبلغ به النبي ﷺ إذا كان يوم الجمعة كان على كل باب من أبواب المسجد ملائكة يكتبون الأول فالأول فإذا خرج الإمام طويت الصحف
Its isnad is sahih. This hadith and the one following it, 7258, were both narrated by Bukhari 2:326 and Muslim 1:235 as a single hadith, through Zuhri from Abu Abdullah Aghar from Abu Hurairah. Muslim then narrated them right after that, also as a single hadith, through Ibn Uyayna from Zuhri from Saeed bin Musayab from Abu Hurairah with the same wording, meaning he did not state its wording but referred back to the one before it. The two hadiths will also come again in the Musnad with the same wording, 7510, 7511, 7752, 7753, through Zuhri from Aghar from Abu Hurairah. Its meaning has also come from Abu Hurairah through other routes, with many chains, much of which will come later, Allah willing. See also what has already passed in the Musnad of Ali bin Abu Talib, 719.