Authentic
Sunan Abu Dawud 1129
I offered the Friday prayer along with him in enclosure. When I uttered the salutation I stood up in my place and prayed. When he went in, he sent me a message saying: Never again do what you have done. When you pray the Friday prayer, you must not join another prayer to it till you have engaged in…
أَنْ لاَ تُوصَلَ صَلاَةٌ بِصَلاَةٍ حَتَّى يَتَكَلَّمَ أَوْ يَخْرُجَ .