´It was narrated that Jabir bin Samurah said:` "I saw the Messenger of Allah (ﷺ) delivering the Khutbah standing up, then he sat down for a while and did not speak, then he stood up and delivered another Khutbah. Whoever tells you that the Prophet (ﷺ) delivered a Khutbah sitting do not believe him."
Hadith Referenceسنن نسائي / كتاب صلاة العيدين / 1584