You pick up your knife and broom because you're getting ready to return home. There'll be a lot of work to do when you return home — cooking, cleaning, fixing stuff — so your knife and broom are sure to come in handy.

For you to return home, your family has to ask the world to 返す (かえ) you to them. You belong at home with your family — the outside world is just borrowing you, and eventually it needs to 返す you and let you return home.