Musnad Abu Ya'la al-Mawsili 2:99

Ishaq ibn Isma'il narrated to us, Sufyan narrated to us, from al-Zuhri, who heard Abu 'Ubayd—meaning the freed slave of Ibn Azhar—say: I witnessed the 'Eid with 'Umar ibn al-Khattab. He began with the prayer before the sermon. And he said: "Indeed, the Messenger of Allah (may Allah bless him and grant him peace) forbade fasting on these two days. As for the day of al-Fitr, it is the breaking of your fast from your fasting. And as for the day of al-Adha, eat from the meat of your sacrificial animals."