And ye shall not swear by my name falsely, neither shalt thou profane the name of thy God: I am the LORD.
Numbers 30:2If a man vow a vow unto the LORD, or swear an oath to bind his soul with a bond; he shall not break his word, he shall do according to all that proceedeth out of his mouth.
Matthew 5:33Again, ye have heard that it hath been said by them of old time, Thou shalt not forswear thyself, but shalt perform unto the Lord thine oaths: