It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) came to Sayyiduna Umar (may Allah be pleased with him), and some of his (peace and blessings be upon him) Companions (may Allah be pleased with them) were with him. He (peace and blessings be upon him) asked: "Are you believers?" They remained silent, three times (this happened); then, last of all, Sayyiduna Umar (may Allah be pleased with him) said: "Yes, we believe in all that you have brought to us, we praise Allah in prosperity, we are patient in trial, and we believe in the decree (qada')." So the Messenger of Allah (peace and blessings be upon him) said: "By the Lord of the Ka'bah, they are believers!"
Imam al-Tabarani (may Allah have mercy on him) said: "No one narrated these two hadiths from Ata except Yusuf bin Maymun, and no one from Yusuf except Abu Yahya al-Himmani; al-Hasan bin Hammad al-Warraq is alone in both of them."
Hadith Referenceالمعجم الأوسط / باب الهاء / 9427
Hadith Gradingمحدثین:إسناده ضعيف لضعف يوسف بن ميمون
Hadith Takhrij«قال الهيثمي: في إسناده يوسف بن ميمون وثقه ابن حبان والأكثر على تضعيفه «مجمع الزوائد ومنبع الفوائد، ج 1، ص 55»» «أخرجه الطبراني فى «الكبير» برقم: 11336»