Okay, Henry senses the power struggle between Locke and Jack, and hits the nail on the head of Locke's insecurity / problem with being in weak or secondary positions.

Remember, when Locke first asks Jack to push the button, he kind of begged him, saying he did not want to be alone, almost a child to Daddy.

But still, do you think Locke is just plain losing it?

He certainly surprised me when he lost his temper and punched out Charlie.
And now, his fit in the hatch kitchen.

Where did Mr. calm philosopher go? Very odd, if you ask me.