Matthew 18:17-20

17And if he shall neglect to hear them, tell it to the church: but if he shall neglect to hear the church, let him be to thee as an heathen and a tax collector. 18Verily I say to you, Whatever ye shall bind on earth shall be bound in heaven: and whatever ye shall loose on earth shall be loosed in heaven. 19Again I say to you, That if two of you shall agree on earth concerning any thing that they shall ask, it shall be done for them by my Father who is in heaven. 20For where two or three are gathered together in my name, there am I in the midst of them.