'Swore' in the Bible

And Saul hearkened to the voice of Jonathan, and Saul swore, As Jehovah liveth, he shall not be put to death!

And David swore again and again, and said, Thy father certainly knows that I have found favour in thy sight: and he has thought, Jonathan shall not know this, lest he be grieved; but truly as Jehovah liveth, and as thy soul liveth, there is but a step between me and death.

And David swore to Saul. And Saul went home; and David and his men went up to the stronghold.

And Saul swore unto her by Jehovah, saying, As Jehovah liveth, there shall no punishment happen to thee for this thing.