'Swear' in the Bible

Now therefore, I pray you, swear unto me by the LORD, since I have shewed you kindness, that ye will also shew kindness unto my father's house, and give me a true token:

And the men said unto her, We will be blameless of this thine oath which thou hast made us swear.

And if thou utter this our business, then we will be quit of thine oath which thou hast made us to swear.

and Joshua maketh with them peace, and maketh with them a covenant, to keep them alive; and swear to them do the princes of the company.

We swear we have done this because we were worried that in the future your descendants would say to our descendants, 'What relationship do you have with the Lord God of Israel?

That ye come not among these nations, these that remain among you; neither make mention of the name of their gods, nor cause to swear by them, neither serve them, nor bow yourselves unto them: