The Messenger of Allah ﷺ used to deliver two khutbahs standing, and he would separate them by sitting. (Using translation from Nasāʾī 1416)  

«أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ يَخْطُبُ خُطْبَتَيْنِ وَهُوَ قَائِمٌ وَكَانَ يَفْصِلُ بَيْنَهُمَا بِجُلُوسٍ»  

The Apostle of Allah ﷺ gave two sermons between which he sat, recited the Qur'an and exhorted the people. (Using translation from Muslim 862a)  

«كَانَتْ لِلنَّبِيِّ ﷺ خُطْبَتَانِ يَجْلِسُ بَيْنَهُمَا يَقْرَأُ الْقُرْآنَ وَيُذَكِّرُ النَّاسَ»