In Book 21, how does Odysseus prove himself to his loyal servants and friends? What promise does he make them?

Odysseus strings the bow, and he shoots the arrow through the handle hole of every axe. He then turns to his son and says, ‘The guest in your hall has not disgraced you. I have not missed the target, nor did it take me long to string the bow. My strength is undiminished, not lessened as the Suitors’ taunts implied. Well now it is time for the Achaeans to eat, while there is light, and afterwards we shall have different entertainment, with song and lyre, fitting for a celebration.’