I could not but believe every word of what he had said.
But on the other hand, she seemed to want to believe every word he said.
But I do not believe a word of what they say.
And no one should ever believe a word he says.
I couldn't make out for the moment whether to believe a word of what he said.
I didn't believe a word of what he was saying.
They didn't believe a word we told them at first.
He did not believe a single word of her story.
How likely was he to believe a word she said then?
She did not seem to believe her own words, though.