Matthew 5:37; Matthew 18:17; Matthew 20:26-27

37 But let your communication be , Yea, yea; Nay, nay: for whatsoever is more than these cometh of evil.
17 And if he shall neglect to hear them, tell it unto the church: but if he neglect to hear the church, let him be unto thee as an heathen man and a publican.
26 But it shall not be so among you: but whosoever will be great among you, let him be your minister; 27 And whosoever will be chief among you, let him be your servant: