(14) باب التَّحِيَّةِ وَالإِمَامُ يَخْطُبُ
Jabir reported that Sulaik Ghatafani came on Friday (for prayer) while the Messenger of Allah (ﷺ) was sitting on the pulpit. Sulaik also sat down before observing prayer. The Apostle of Allah (ﷺ) said:
Have you observed two rak'ahs? He said: No. He (the Holy Prophet) said: Stand and observe them
Reference: Sahih Muslim 875 f
In-book reference: Book 7, Hadith 73
USC-MSA web (English) reference(deprecated numbering scheme): Book 4, Hadith 1902