Matthew 5:33

5:33 "Again you have heard that it was said to them of old time, 'You shall not make false vows, but shall perform to the Lord your vows,'
-World English Bible

Other Translation

5:33 Again, 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:
-King James Version