It is narrated from Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) that he said: "I heard the Messenger of Allah (peace and blessings be upon him) saying: 'Indeed, every nation has a trustworthy one, and the trustworthy one of this nation is Sayyiduna Abu Ubaydah bin al-Jarrah (may Allah be pleased with him).'"
This hadith is narrated from Sayyiduna Abdullah (bin Arqam) (may Allah be pleased with him), from Sayyiduna Umar (may Allah be pleased with him), only with this chain, and Muhammad bin Ishaq (may Allah have mercy on him) is alone in narrating it.
Hadith Referenceالمعجم الأوسط / باب الألف / 866
Hadith Takhrij«أخرجه أحمد فى «مسنده» برقم: 238، وأبو يعلى فى «مسنده» برقم: 228، والبزار فى «مسنده» برقم: 114، 115، 117»