"Serve the least"

A Father serves all, his labor is to provide for his family, nurture, protect, and watch over them. And so Our Father did the same, and His Son did the same here, by demonstrating. "The least" as in one's children, the father, the head of a family does the same, acts as God and the Son in his own small way.

Why Christ Came Poor

The Jews were scandalized that Christ appeared as a poor man, but that he should appear as a King.

Christian tradition teaches that God is infinitely above man, and that by descending to be born as a man, Christ raised humans to the possibility of divination and become gods (Sons of God) through Christ.

Christ came as the humblest of men, poorest, born in a manager among animals, to represent this miracle - the miracle of raising even the lowliest of human nature to the status of child of God. If Christ has come as a wealthy man, or King, even those states would still be infinitely below and the glory but a poor reflection of God's own glory - so he descended not just to be born as any man, but the humblest of men.