Matthew 5:36
King James Version
“Neither shalt thou swear by thy head, because thou canst not make one hair white or black.”
Context
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:
34But I say unto you, Swear not at all; neither by heaven; for it is God’s throne:
35Nor by the earth; for it is his footstool: neither by Jerusalem; for it is the city of the great King.
36Neither shalt thou swear by thy head, because thou canst not make one hair white or black.
37But let your communication be, Yea, yea; Nay, nay: for whatsoever is more than these cometh of evil.
38Ye have heard that it hath been said, An eye for an eye, and a tooth for a tooth:
39But I say unto you, That ye resist not evil: but whosoever shall smite thee on thy right cheek, turn to him the other also.