In two ways, we are one: in our essence, and in our character.

In our essence, we are all one soul, with one origin.

In our character, we are all complementary to each other, none of us complete, each one contributing what the other lacks, each one adding his touch of perfection to his fellow. Like a massive jigsaw puzzle, we fit together to make a single perfect whole.

None of us is perfect without the rest of us.
And the rest of us are incomplete when a single individual is missing.

לקו״ש ח״ד ע׳ 1142 ואילך. ספר הערכין חב״ד ח״א ע׳ תרי״ט. ובזה יובן מ״ש ד״ה ואתה תצוה סי״א בסוגריים.