Silsilat al-Ahadith al-Sahihah

It is narrated from Sayyiduna Uqbah bin Amir al-Juhani (may Allah be pleased with him) that the Noble Prophet (peace and blessings of Allah be upon him) said: “Your reviling (each other) regarding lineage is not a matter of shame or disgrace for anyone, because you are all the children of Adam, and you are less than a full measure (i.e., none of you is perfect and everyone has some deficiency). And no one has any superiority or excellence over another except on the basis of religion and righteous deeds. It is sufficient for a man (to be considered bad) that he is foul-mouthed, ill-spoken, ill-mannered, miserly, and cowardly.”