What is the authenticity of the saying, "No non-Arab has ever shown compassion to an Arab," and is it a Prophetic Hadith or a common saying, and what does it mean?

There is no origin for this statement in the hadith or in reliable reference books. It has been authentically reported from the Prophet, peace and blessings be upon him, that he said: "O people, verily your Lord is one and your father is one. Verily, there is no superiority for an Arab over a non-Arab, nor for a non-Arab over an Arab, nor for a red over a black, nor for a black over a red, except by piety."