The one universal thing that makes people the same is that we all originated in modern day Africa, meaning we are all African. Which means there is no white and black, no lower and no higher. So, everyone is basically the same person here. Even though we have different faces, colors, backgrounds that all doesn't contribute to our distinctive homes. You can't call someone African just because they look brown or black you can call someone African because they were born with you in modern day Africa.
It is significant because a prominent leader was suggesting that the unequal treatment of African Americans was in direct opposition to the principles of the Declaration of Independence.