Answer:
I have many feathers to help me fly. I have a body and head, but I'm not alive. It is your strength which determines how far I go. You can hold me in your hand, but I'm never thrown.
You use a knife to slice my head. And weep beside me when I am dead.
Useful tool for who in darkness dwell. Within you, corrupting like a deadly spell.
What is it that you must give before you can keep it.
What do you use to hoe a row, slay a foe, and wring with woe?
They are many and one, they wave and they drum, Used to cover a state, they go with you everywhere.