Sahih Muslim 883a
'Umar b. 'Ata' b. Abu Khuwar said that Nafi' b. Jubair sent him to al- Sa'ib the son of Namir's sister with a view to asking him about what he had seen in the prayer of Mu'awiya. He said: Yes, I observed the Jumu'a prayer along with him in Maqsura and when the Imam pronounced salutation I stood up at my place and observed (Sunan rak'ahs). As he entered (the apartment) he sent for me and said: Do not repeat what you have done. Whenever you have observed the Jumu'a prayer, do not observe (Sunan prayer) till you, have talked or got out For the Messenger of Allah ﷺ had ordered us to do this and not to combine two (types of) prayers without talking of going out.
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا غُنْدَرٌ، عَنِ ابْنِ جُرَيْجٍ، قَالَ أَخْبَرَنِي عُمَرُ، بْنُ عَطَاءِ بْنِ أَبِي الْخُوَارِ أَنَّ نَافِعَ بْنَ جُبَيْرٍ، أَرْسَلَهُ إِلَى السَّائِبِ ابْنِ أُخْتِ نَمِرٍ يَسْأَلُهُ عَنْ شَىْءٍ، رَآهُ مِنْهُ مُعَاوِيَةُ فِي الصَّلاَةِ فَقَالَ نَعَمْ . صَلَّيْتُ مَعَهُ الْجُمُعَةَ فِي الْمَقْصُورَةِ فَلَمَّا سَلَّمَ الإِمَامُ قُمْتُ فِي مَقَامِي فَصَلَّيْتُ فَلَمَّا دَخَلَ أَرْسَلَ إِلَىَّ فَقَالَ لاَ تَعُدْ لِمَا فَعَلْتَ إِذَا صَلَّيْتَ الْجُمُعَةَ فَلاَ تَصِلْهَا بِصَلاَةٍ حَتَّى تَكَلَّمَ أَوْ تَخْرُجَ فَإِنَّ رَسُولَ اللَّهِ ﷺ أَمَرَنَا بِذَلِكَ أَنْ لاَ تُوصَلَ صَلاَةٌ حَتَّى نَتَكَلَّمَ أَوْ نَخْرُجَ .