It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever hated Sayyiduna Umar (may Allah be pleased with him) has hated me, and whoever loved Sayyiduna Umar (may Allah be pleased with him) has loved me. Allah Almighty boasts about all the people in general on the evening of Arafah, and boasts about Sayyiduna Umar (may Allah be pleased with him) in particular. Indeed, Allah has never sent a Prophet except that there was a muhaddath (one who is inspired) in his Ummah; so if there is any one of them in my Ummah, it is Sayyiduna Umar (may Allah be pleased with him)."
The Companions said: "O Messenger of Allah, what is a muhaddath like?" He (peace and blessings be upon him) said: "The angels speak upon his tongue."
Imam al-Tabarani (may Allah have mercy on him) said: "No one narrated this hadith from Sayyiduna Abu Sa'id (may Allah be pleased with him) except al-Hasan (may Allah have mercy on him), and from al-Hasan (may Allah have mercy on him) only his servant Abu Sa'd (may Allah have mercy on him), and from Abu Sa'd (may Allah have mercy on him) only Muhammad bin Muhajir (may Allah have mercy on him); Isma'il bin Ayyash (may Allah have mercy on him) is alone in narrating it."
Hadith Referenceالمعجم الأوسط / باب الميم / 6726
Hadith Gradingمحدثین:فيه أبو سعد خادم الحسن البصري لم يُعرف، وبقية رجاله ثقات
Hadith Takhrij«قال الهيثمي: فيه أبو سعد خادم الحسن البصري ولم أعرفه وبقية رجاله ثقات «مجمع الزوائد ومنبع الفوائد، ج 9، ص 69»»