KING HENRY Far be the thought of this from Henry's heart, To make a shambles of the Parliament House! Cousin of Exeter, frowns, words, and threats Shall be the war that Henry means to use. (1.1.71-74)
York and his team and ready to duke it out, and so is Clifford. Henry, however, wants to fight using language, not weapons. He thinks it's a disgrace to use other weapons in parliament. He's also banking on the fact that he's the king, and thinks that should count for something in a war of words.
KING HENRY I know not what to say; my title's weak.— Tell me, may not a king adopt an heir? (1.1.138-139)
Whoops. Henry readily admits to us (in an aside) that he has been outsmarted. We can see that he has no real power, linguistic or otherwise.
KING HENRY Have done with words, my lords, and hear me speak. QUEEN MARGARET Defy them then, or else hold close thy lips. KING HENRY I prithee, give no limits to my tongue. I am a king and privileged to speak. (2.2.119-123)
Margaret's never shy of telling her hubby what she thinks, even in a room full of nobles. She snaps at him because he can't command any authority with Edward and his crew. She points out that Henry has no power, because no one listens to him. Again, it's through language—or the inability to speak—that we understand who's got the power... and who doesn't.
RICHARD Why, I can smile, and murder whiles I smile, And cry 'Content' to that which grieves my heart, And wet my cheeks with artificial tears, And frame my face to all occasions. (3.2.184-187)
Richard claims he can pretend to be good when he's really bad and thereby throw everyone off. It sounds like Richard's a great actor, and we can see that he's great with language. He's the one who gets the long speeches and the spotlight in this play, and he's the one who subtly controls others from the background.
QUEEN MARGARET Those gracious words revive my drooping thoughts And give my tongue-tied sorrows leave to speak. (3.3.24-25)
A powerful woman, Margaret's really good with words. In fact, that's what Edward and his camp are afraid of. They know Margaret is convincing with her language, and they're scared she'll convince King Lewis to send some troops her way.
KING EDWARD Her looks doth argue her replete with modesty; Her words do show her wit incomparable; All her perfections challenge sovereignty. One way or other, she is for a king... (3.2.84-87)
Edward likes Lady Grey when she comes to visit him. It's partly her virtue and modesty, but partly her "wit" and "words" that he finds attractive. These words must be compelling, because Edward risks his kingdom and his relationship with his brothers for her.
MONTGOMERY What talk you of debating? In few words, If you'll not here proclaim yourself our king, I'll leave you to your fortune and be gone (4.7.53-55)
After Edward has escaped, Montgomery wants to know if he will fight for the crown. He's sick of the old war-of-words game; he wants real action from his king. It's clear that everyone automatically understands that having a good command of language is part of the package deal when it comes to being king. Whoever's got the words has the power. Montgomery wants to move past that once and for all.
KING EDWARD Now here a period of tumultuous broils. Away with Oxford to Hames Castle straight. For Somerset, off with his guilty head. Go, bear them hence. I will not hear them speak. (5.5.1-4)
Edward has just won the war. The first thing he does? He gets rid of his enemies before they can disrupt him again. We're especially interested in fact that he doesn't even let his enemies speak. Words equal power, and he doesn't want them having any of that.
KING HENRY Ah, kill me with thy weapon, not with words!
My breast can better brook thy dagger's point. (5.6.27-28)
Henry knows he can't win in a war of words. Richard comes in talking a big game, and Henry tells him to prove it. Sadly, he does. It turns out Richard is good with weapons and with his tongue; that's a double whammy.
KING HENRY The owl shrieked at thy birth, an evil sign; The night-crow cried, aboding luckless time; Dogs howled, and hideous tempest shook down trees; The raven rooked her on the chimney's top; And chatt'ring pies in dismal discords sung; Thy mother felt more than a mother's pain, And yet brought forth less than a mother's hope, To wit, an indigested and deformèd lump, Not like the fruit of such a goodly tree. Teeth hadst thou in thy head when thou wast born To signify thou cam'st to bite the world. (5.6.45-55)
Henry suddenly becomes the king of smack-talk right before Richard kills him. It's the one time Henry seems to have command of language, but it doesn't do him any good; it's too late. His words do have an effect on Richard, though… and on the audience. His last ditch effort at a prophecy comes true, and Richard tells us he's about to kick off his evil plan after Henry dies. Did Henry place a curse on Richard? Does Richard meet his eventual doom because Henry told him he would?