Don’t be afraid of the other person because he is different from you. There is far more in common between any two human beings than there are differences.
As for those differences, think of them as the hooks that hold us together, the reasons for needing one another.
Indeed, differences are the thing we all have most in common.
The Rebbe was talking to children, and discussing relationships between Jews and non-Jews.

Rising Above Our Differences Abraham, Moses and kabbalists after them taught their followers how to live cooperatively in unity.
Through inner mental attitude they rose above their egoistic differences to live in G_d's image of mutual care of the others in one harmonious system.
We need to aspire to this unity once again to set the example. Then all humanity will rise to a new level of existence as one harmonious system.