A strength to harm is perilous in the hand of an ambitious head.

The stone often recoils on the head of the thrower.

One man with a head on his shoulders is worth a dozen without.

I know I have but the body of a weak and feeble woman, but I have the heart and stomach of a king, and of a king of England too.

My mortal foe can no ways wish me a greater harm than England's hate; neither should death be less welcome unto me than such a mishap betide me.

You are ambitious, which, within reasonable bounds, does good rather than harm.