“I witnessed the Eid prayer with the Messenger of Allah—may Allah’s peace and blessings be upon him. When he finished the prayer, he said: ‘We will deliver a sermon, so whoever wishes to sit for the sermon, let him sit, and whoever wishes to leave, let him leave.’”

Narrated by Abū Dāwūd (no. 1155), with the wording being his, and by al-Nasāʾī (no. 1571) and Ibn Mājah (no. 1290), from the ḥadīth of ʿAbd Allāh ibn al-Sāʾib—may Allah be pleased with him.
Authenticated in Ṣaḥīḥ al-Jāmiʿ (no. 2289) and Ṣaḥīḥ Sunan Abī Dāwūd (no. 1048).

Brief Explanation of the Hadith

The Eid sermon is among the manifest symbols of Islam, and attending it is legislated due to what it contains of manifesting the rites of the religion and the gathering of Muslims upon goodness.
In this ḥadīth, ʿAbd Allāh ibn al-Sāʾib—may Allah be pleased with him—reports that he witnessed the Eid prayer with the Prophet—may Allah’s peace and blessings be upon him. When he finished the prayer, he informed them that he would deliver a sermon, then gave them the choice between remaining seated to listen to the sermon or departing. This indicates that the Eid sermon is not obligatory like the Friday sermon, and that listening to it is recommended rather than required. Nevertheless, remaining seated to listen and benefit is preferable, as it involves hearing remembrance and admonition and conforms to the Sunnah.
And in the ḥadīth there is an illustration of the ease of the Sharīʿah, its consideration of people’s circumstances, and the removal of hardship from them.