And in King Henry the Fourth Act

And in King Henry the Fourth Act

And in King Henry the Fourth Act.
I am as vigilant as a cat to steal cream.

And in King Henry the Fourth, Act IV., Scene 2, of its pilfering ways, Falstaff cries out:

I am as vigilant as a cat to steal cream.

While Lady Macbeth points to the uncertain, timid, cautious habits of the cat, amounting almost to cowardice:

Letting I dare not wait upon I would,
Like the poor cat i' the adage.