1 Corinthians 12:13, 25-26

Some of us are Jews, some are Gentiles, some are slaves, and some are free. But we have all been baptized into one body by one Spirit, and we all share the same Spirit.

This makes for harmony among the members, so that all the members care for each other. If one part suffers, all the parts suffer with it, and if one part is honored, all the parts are glad.