Ibn Mas'ud (may Allah be pleased with him) said: When the soul of the Prophet (peace and blessings be upon him) was taken, the Ansar said: There should be one leader from us and one from you. Then Umar (may Allah be pleased with him) came and said: "O Ansar! Do you not know that the Prophet (peace and blessings be upon him) put Abu Bakr (may Allah be pleased with him) forward to lead the prayer? So which of you would willingly go ahead of Abu Bakr (may Allah be pleased with him)?" The Ansar said: "We seek refuge in Allah from going ahead of Abu Bakr (may Allah be pleased with him)."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قتال أهل البغي / 16586