Sware [verb]

He was then required to swear by all the gods, and by the dreaded Erinnys, that he had spoken truly.

I've come to see you for two minutes; I swear I mean you no harm.

He tried to swear Edith and me to secrecy, but we refused to be sworn.

It don't do 'em any good, but just the same they all swear they're innocent.

Will you swear that the message that went with it had nothing to do with the Lenni-Lenape?'

But as to Samuel's return, that I can swear to, and so can Josiah.

How can you swear, then, that the prisoner made the assault?

True; but I'll swear the language of my looks has been unequivocal, if that is what you mean.

I swear that, laying aside all other ends, to that sole purpose I will devote my days.

He wanted to curse and swear, and had to clap his hands on his mouth to prevent it.