'Swear' in the Bible

Or if a soul swear, pronouncing with his lips to do evil, or to do good, whatsoever it be that a man shall pronounce with an oath, and it be hid from him; when he knoweth of it, then he shall be guilty in one of these.

or have found that which was lost, and deal falsely therein, and swear to a lie; in any of all these things that a man doeth, sinning therein;

And ye shall not swear by my name falsely, neither shalt thou profane the name of thy God: I am the LORD.