It is narrated from Imam al-Hasan al-Basri (may Allah have mercy on him) that Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) objected to Sayyiduna Ubayy bin Ka'b's (may Allah be pleased with him) recitation of a verse, so Sayyiduna Ubayy (may Allah be pleased with him) said: "I certainly heard this verse directly from the Messenger of Allah (peace and blessings be upon him), while you, O Umar, were kept unaware of it by buying, selling and trading in the market of al-Baqi'." At this Sayyiduna Umar (may Allah be pleased with him) said: "You have spoken the truth. My aim was only to test you people, whether there is anyone among you who can speak the truth, for there is no good in a ruler before whom the truth is not spoken and who does not himself speak the truth."
This narration is munqati' (broken).
Hadith Referenceالمطالب العالية بزوائد المسانيد الثمانية / كتاب الزهد والرقائق / 3290
Hadith Gradingمحدثین:إسناده منقطع
Hadith Takhrij«حکم الحدیث المطالب العالیہ محققاً تنسیق د. سعد بن ناصر بن عبد العزيز الشَّثري- مکتبہ شاملہ :قال ابن حجر: هَذَا مُنْقَطِعٌ . » «انفرد به المصنف من هذا الطريق»