Silsilat al-Ahadith al-Sahihah

It is narrated from Abu Mas'ud (may Allah be pleased with him), he says: I was asked, "What did you hear the Messenger of Allah (peace and blessings of Allah be upon him) say regarding «زعموا»?" He says that the Messenger of Allah (peace and blessings of Allah be upon him) said: "«زعموا» is a bad mount for a man, (i.e., it is a bad habitual phrase)."