Matthew 18:17-20

17But if he will not listen to them, tell it to the assembly; and if also he will not listen to the assembly, let him be to thee as one of the nations and a tax-gatherer.

18Verily I say to you, Whatsoever ye shall bind on the earth shall be bound in heaven, and whatsoever ye shall loose on the earth shall be loosed in heaven.

19Again I say to you, that if two of you shall agree on the earth concerning any matter, whatsoever it may be that they shall ask, it shall come to them from my Father who is in [the] heavens.

20For where two or three are gathered together unto my name, there am I in the midst of them.