Hadith 1574
Chapter 18: Imam standing during the Khutbah - كتاب صلاة العيدين
أَخْبَرَنَا إِسْمَاعِيلُ بْنُ مَسْعُودٍ، قَالَ حَدَّثَنَا خَالِدٌ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ سِمَاكٍ، قَالَ سَأَلْتُ جَابِرًا أَكَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَخْطُبُ قَائِمًا قَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَخْطُبُ قَائِمًا ثُمَّ يَقْعُدُ قَعْدَةً ثُمَّ يَقُومُ .
It was narrated that Simak said:
"I asked Jabir: 'Did the Messenger of Allah (ﷺ) deliver the Khutbah standing?' He said: 'The Messenger of Allah (ﷺ) used to deliver the Khutbah standing, then he would sit for a while, then stand up again.'"
Reference : Sunan an-Nasa'i 1574
In-book reference : Book 19, Hadith 19